I just finished ripping my engine bay all the way down to paint it and I laid my old TBI harness on the ground.... I have an 87 TPI system with a factory wiring harness (My camaro originally is a 91 TBI 305). I can tell just by looking at the harnesses that I need to combine to get a complete TPI harness. What I really need right now is to be pointed towards some web sites or books that will give me a good wiring diagram.... my Haynes manual is not getting it done.

get a shop manual from helm. it has complete wire harness breakdowns for the whole car. Also i would seriously consider changing the tuned port to a speed density setup. it will be a hell of a lot easier to swap into a 91 than a mass air system.

Hey, i did this exact swap. The book that helped me the most was a book by Choco Munday. Its called "TUNED PORT INJECTION" it has every diagram you need. Its only good for 87 to 89 tuned ports. I also made my own diagram to join the 2 harnesses. If you have any questions, don't hesitate to ask. an 87 or 88 GM camaro manual also came in very handy for me.