Depending on model and year there are 3-4 systems that people remove or disable (Air pump, EGR, EVAP, Cat's). Unfortunately none really buy a lot of performance and can cause problems selling or when relocating to a testing geography. Need your year and model info. R U trying to get it emission tested ? If stuff was yanked and thrown out it could get expensive replacing it.
We have 2 resources to help you. Both in 4th gen section. First the 4th gen parts book which will have exploded views and part numbers.
Then we have the factory 94 service manual. Look for thread titled "GM service manuals.
Now for missing parts. I would look on craigslist. Expand your search as far as your willing to drive. Look for people parting out 4th gens. They probably won't list emission stuff, so you will have to contact sellers and ask if they have it.
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