I would say go for it Neal, if you think it can work. I would like to see a WRX conversion to an 02' RS. AFAIK no one has done it yet. I think the WRX turbo would be too small, but on the contrary you would probably get boost very soon. I imagine this would be similar to the Legacy turbo setup that some guys (and soon myself) run on their RS's. As far as the intercooler working, it probably will. If guys can stuff them into their GC8's with quite a bit of custom work (63Alpine on i-club), then I imagine the REX intercooler should fit fine, though do not quote me on that because I haven't seen it done. I do know that the EJ20 engine sits farther forward than the EJ25, but im not sure if they carried this over into the new body style Scoobie's. This would be a fun project and I *think it could be done for relatively cheap, considering the plethora of used WRX turbo parts for sale. Good luck.
Graham
Oh, and definetly run that J&S.
Graham
Oh, and definetly run that J&S.