Alright. So. Here we go. I do a lot of working with clusters. Mostly because i enjoy taking nice things and tearing them apart, but also because clusters are really cool. They are the main thing (at least in our lovely GCs) we as the human visually interact with in the car and they tell us a lot about what our car is doing and what we as are doing. Different clusters can give a car a completely different driving experience, this is most noted by the fact that STis have much different clusters than base Imprezas. There's gotta be a reason for that.
Anyways, all of the feely feel things aside the internet always seems to go up in arms when we look at the difference between a 98 style cluster and a 99-01 style cluster. These different types are the V4 style and the V5/6 style. Now, we all know the difference is that they either have white plugs or green plugs... but there's a hell of a lot more to it than that.
Let's start by making clear which is what. Below we have a picture of a V4 STi type R, this and other models in the 98 year are all Subaru's bastard children. The car has the same exterior as the V3 STi, the same engine, but the interior was upgraded.. sorta. My guess is that there was some disagreement between departments at Subaru, deadlines weren't met, and the rice hit in the fan and the V4 STi was flumped out.
Next we have the V5 STi as well as the V6 STi. More similar than the V3/4 and they got a new bumper, spoiler, engine, you name it. But it still had the same interior as the V4.... kinda.
Alright, so now we have an idea of which cars are what. Let's dive into the difference between the clusters.
So below I have a picture of my personal V4 style cluster as well as a V5/6 style cluster. The V5/6 style cluster is just a WRX cluster, but aside from a different tach overlay, they are identical. On the other hand, the only V4 cluster I had was a 10k/280kph cluster... so in the name of education and as I mentioned above, I like to tear nice things apart, we are gonna rip into to see what's up. They are identical to the other V4 styles for sake of the overlay and a few other negligible details.
We can see easily the different style of connector, as well as the copper ribbon routing as opposed to PCB style. The V4 rocks the ribbon, and the V5/6 rocks the PCB.
Here we pull them apart a little more and we can see some differences.
On the top we see the V5/6 style that uses a single controller to control EVERYTHING. Clock, speed, tach, odo, it all goes through the one controller.
Below we see the tach control board (left) and the speedo/odo control board (right) that the V4 STi style has. I should also note that in order to get to these individual PCBs I had to pull the cluster completely apart.
Let's have a look at the front sides of the V4 style boards as they have a lot going on. The V5/6 doesn't have much else on the other side of the boards so I left them out.
Here we see some of my lovely rigging.. ignore that. So what he have here are two EXTREMELY outdated microcontrollers... so outdated that I can't even find a datasheet for them. They individually control each motor and each get a very different input unlike the V5/6 where a single controller takes care of all the work.
The reason for the switch? Well, the V5/6 style is clearly more technologically advanced for the time period, and that same controller and style was used all the up until 2004. CHA CHING sooooooo much production money saved. The 98 style seems like a half assed way of getting a digital VSS and odometer on the car without a real plan to continue manufacturing this style of cluster. I dunno.. that's speculation. I'm guessing some people got fired over this choice.
Clocks. They do the same job... kind of... but not really. Like at all. Here is a picture mostly showing off the separate V4 style clock, and the integrated V5/6 style clock. We can see some circuitry for the V4 clock, and we can see PCB traces for the V5/6 clock that come from the main controller.
It's pretty neat to also note that the V4 style clocks we able to be changed by the hour and by the minute, where as the V5/6 style clocks are just a running + or - minute when setting the clock. This is also noted in the picture below comparing the H and M vs + and - buttons that poke through for the driver to set.
Alright.. moving on. Motors and needles.
Below shows a V5/6 style motor actually pulled off from a UKDM 160mph cluster. Don't ask why it's off. It's a long story. The part you care about is that all clusters 99-01 whether it was the tach motor or speedo motor or an RS cluster or an STi or WRX or Turbo 2000 or Impreza L or whatever models you imagination can come up with... the motors were the same. This was not the case with the V4 style clusters. Below is a picture comparing tach motors.
Left is the V5/6 and right is the V4. The V4 one is very much so integrated with the PCB, and uses a really small and flat winding. The V5/6 motor is more cylindrical and uses a more cylinder like winding. Hmm. Neat. Different style motors means different means of controlling them... which.. hey! We saw that above!
Needles. Not too interesting here, but V5/6 (left) is a splined needle, where the V4 (right) is not. Again, different motors, different methods of output driving.
Moving right back along on things are the minuscule, but I think are neat differences from a production standpoint.
Below we see both the insert styles. The V4 style (bottom) doesn't have alignment dowels on the bottom and a slightly boxier curve than the V5/6 style (top). Probably different suppliers and different machining/moulding between production runs.
As we dive into the inserts a bit further we can see a bit of a difference between the overlays around the tach needle area. The V4 style (left) has a slightly rotated design to accommodate the slightly different motor we looked at above. Kinda neat.
Connectors and wiring... as in.. the stuff you actually care about. There's a reason why I put it last so you wouldn't read it first and then not care about the clock button differences enough to read about em!
Below is a picture of the two different style connectors. V4 is the ribbon style and V5/6 is the PCB style. We ALL know this difference.
The PCB style is easily understood, but the ribbon style still blows my mind. Why the HELLLLLLLL did they use it? I guess it was the easiest way to seperate the controlling of the speedo/tach/clock from the lighting on the cluster. It's a cheap solution to easy on/off lighting and we can see all the bulbs plugged into the ribbon in a picture above.
What goes with connectors? Wiring harnesses.
V4 style cluster intermediate harness:
V5/6 Style cluster intermediate harness, which I should note also includes the connectors for the Hazard and Defrost switch, where the V4 style does not.
It's very obvious to tell that the V4 and V5/6 wiring harness difference are SUPER different because of a complete phase change in Subaru's engines and OBD standards. The clusters are effected by this change too. Online in other places you can find pinouts to repin and see the differences.. I don't really want to go over that here because that's a whole other thread on it's own.
Here are the two intermediate to main bulkhead harness connectors. V4 on the left, V5/6 on the right.
So there you have it. All the differences between styles I could come up with, and this post URL should be the only thing you ever have to show anyone when they ask "will a V4 cluster work in my 99 RS" or any of the other variations people always seem to ask me.
If I had any advice, I will 11/10 times tell you to convert to the V5/6 style cluster. It's much more manageable and reliable design, and it's easier to play with and do neat thing with. V4..... I still don't know how or why you exist.
Anyways, all of the feely feel things aside the internet always seems to go up in arms when we look at the difference between a 98 style cluster and a 99-01 style cluster. These different types are the V4 style and the V5/6 style. Now, we all know the difference is that they either have white plugs or green plugs... but there's a hell of a lot more to it than that.
Let's start by making clear which is what. Below we have a picture of a V4 STi type R, this and other models in the 98 year are all Subaru's bastard children. The car has the same exterior as the V3 STi, the same engine, but the interior was upgraded.. sorta. My guess is that there was some disagreement between departments at Subaru, deadlines weren't met, and the rice hit in the fan and the V4 STi was flumped out.

Next we have the V5 STi as well as the V6 STi. More similar than the V3/4 and they got a new bumper, spoiler, engine, you name it. But it still had the same interior as the V4.... kinda.

Alright, so now we have an idea of which cars are what. Let's dive into the difference between the clusters.
So below I have a picture of my personal V4 style cluster as well as a V5/6 style cluster. The V5/6 style cluster is just a WRX cluster, but aside from a different tach overlay, they are identical. On the other hand, the only V4 cluster I had was a 10k/280kph cluster... so in the name of education and as I mentioned above, I like to tear nice things apart, we are gonna rip into to see what's up. They are identical to the other V4 styles for sake of the overlay and a few other negligible details.

We can see easily the different style of connector, as well as the copper ribbon routing as opposed to PCB style. The V4 rocks the ribbon, and the V5/6 rocks the PCB.
Here we pull them apart a little more and we can see some differences.

On the top we see the V5/6 style that uses a single controller to control EVERYTHING. Clock, speed, tach, odo, it all goes through the one controller.
Below we see the tach control board (left) and the speedo/odo control board (right) that the V4 STi style has. I should also note that in order to get to these individual PCBs I had to pull the cluster completely apart.
Let's have a look at the front sides of the V4 style boards as they have a lot going on. The V5/6 doesn't have much else on the other side of the boards so I left them out.

Here we see some of my lovely rigging.. ignore that. So what he have here are two EXTREMELY outdated microcontrollers... so outdated that I can't even find a datasheet for them. They individually control each motor and each get a very different input unlike the V5/6 where a single controller takes care of all the work.
The reason for the switch? Well, the V5/6 style is clearly more technologically advanced for the time period, and that same controller and style was used all the up until 2004. CHA CHING sooooooo much production money saved. The 98 style seems like a half assed way of getting a digital VSS and odometer on the car without a real plan to continue manufacturing this style of cluster. I dunno.. that's speculation. I'm guessing some people got fired over this choice.
Clocks. They do the same job... kind of... but not really. Like at all. Here is a picture mostly showing off the separate V4 style clock, and the integrated V5/6 style clock. We can see some circuitry for the V4 clock, and we can see PCB traces for the V5/6 clock that come from the main controller.

It's pretty neat to also note that the V4 style clocks we able to be changed by the hour and by the minute, where as the V5/6 style clocks are just a running + or - minute when setting the clock. This is also noted in the picture below comparing the H and M vs + and - buttons that poke through for the driver to set.

Alright.. moving on. Motors and needles.
Below shows a V5/6 style motor actually pulled off from a UKDM 160mph cluster. Don't ask why it's off. It's a long story. The part you care about is that all clusters 99-01 whether it was the tach motor or speedo motor or an RS cluster or an STi or WRX or Turbo 2000 or Impreza L or whatever models you imagination can come up with... the motors were the same. This was not the case with the V4 style clusters. Below is a picture comparing tach motors.

Left is the V5/6 and right is the V4. The V4 one is very much so integrated with the PCB, and uses a really small and flat winding. The V5/6 motor is more cylindrical and uses a more cylinder like winding. Hmm. Neat. Different style motors means different means of controlling them... which.. hey! We saw that above!
Needles. Not too interesting here, but V5/6 (left) is a splined needle, where the V4 (right) is not. Again, different motors, different methods of output driving.

Moving right back along on things are the minuscule, but I think are neat differences from a production standpoint.
Below we see both the insert styles. The V4 style (bottom) doesn't have alignment dowels on the bottom and a slightly boxier curve than the V5/6 style (top). Probably different suppliers and different machining/moulding between production runs.

As we dive into the inserts a bit further we can see a bit of a difference between the overlays around the tach needle area. The V4 style (left) has a slightly rotated design to accommodate the slightly different motor we looked at above. Kinda neat.

Connectors and wiring... as in.. the stuff you actually care about. There's a reason why I put it last so you wouldn't read it first and then not care about the clock button differences enough to read about em!
Below is a picture of the two different style connectors. V4 is the ribbon style and V5/6 is the PCB style. We ALL know this difference.

The PCB style is easily understood, but the ribbon style still blows my mind. Why the HELLLLLLLL did they use it? I guess it was the easiest way to seperate the controlling of the speedo/tach/clock from the lighting on the cluster. It's a cheap solution to easy on/off lighting and we can see all the bulbs plugged into the ribbon in a picture above.
What goes with connectors? Wiring harnesses.
V4 style cluster intermediate harness:

V5/6 Style cluster intermediate harness, which I should note also includes the connectors for the Hazard and Defrost switch, where the V4 style does not.

It's very obvious to tell that the V4 and V5/6 wiring harness difference are SUPER different because of a complete phase change in Subaru's engines and OBD standards. The clusters are effected by this change too. Online in other places you can find pinouts to repin and see the differences.. I don't really want to go over that here because that's a whole other thread on it's own.
Here are the two intermediate to main bulkhead harness connectors. V4 on the left, V5/6 on the right.

So there you have it. All the differences between styles I could come up with, and this post URL should be the only thing you ever have to show anyone when they ask "will a V4 cluster work in my 99 RS" or any of the other variations people always seem to ask me.
If I had any advice, I will 11/10 times tell you to convert to the V5/6 style cluster. It's much more manageable and reliable design, and it's easier to play with and do neat thing with. V4..... I still don't know how or why you exist.