ok:
no sensors after cats, means you can remove the cats (if you want- free power)
with regards to the canister and egr (recirculating value thingy) best thing to do is unplug the electronics going to them and stop them working (to simulate you taking them off) and unplug and block the pipes you can, drive the car a bit like this to see if there are any adverse effects, check engine lights and such. If all is ok, then you can permanently remove them and get some LT headers. I think being a 91 you may get away with it, as the old ecu didnt have all the checks etc, and the pipes and stuff etc my be mechanical and vacuum operated, so taking them off wont do any harm. Its only when they are electronic it could cause problems. I know my 99 needs all emissions stuff tuned out
I have just found out also that some 91 had EGR with temp sensors and some without, the former when removed give a code after a few minutes. Also it would be recommended to get a tune after you do remove it as it can cause problem (these are same as i have heard for my 99)
http://www.thirdgen.org/egrdiagnose
There is a company in US called PCMforless, they might be able to get you a ecu with it all deleted they are typically about $150 + shipping
http://www.pcmforless.com/index.php?opt ... &Itemid=40
let me know how you get on
