i cant weld SS, it needs to be mild steel because i use flux core wire. i dont have gas now.you can buy a resonator for decently cheap online and just have it welded into your midpipe.
http://stores.channeladvisor.com/verociousmotorsports/items/item.aspx?itemid=3038537
thats the resonator that i'm going to go with when i get the test pipe so its not as loud but not as restricted as a high flow.