Lurker from way back getting back into Third gens. Here is what I have a computer,wiring harness,dual fans,gas tank from a 89 IROC too far gone to fix. 88 350 TPI drive train,and a 91 305 TBI car. What's involved with getting this swap done? Thanks for your help.

 

I did almost the same swap. Ok you can leave the tank from the RS in place just replace the fuel pump with a high volume, high pressure unit from walbro, Holley ect... Change the fuel filter, the fuel lines will work all the way to front of the car. On the drivers side on the frame rail ( you can see them clearly under hood) there are the fuel lines, disconnect the lines that run from there to the TBI system. You will need the factory TPI lines that run from the TPI rails to the frame rails. Disconnect and label everything from the TBI system. Pull the engine, then pull the TBI computer out and feed the wiring harness throught the hole in the kickpanel and up in the fender and out into the engine bay. Run you new harness ( I used a painless harness) the only wires you will need ( off the top of my head) are the brown with a white strip (fuel pump), pink with a white stripe ( Ign. pwr.). Put your new harness in, then the 350 and hook everything up. You will need to replace the ingnition module ( drivers side by the firewall) with a 350 TPI one. Thats about it. Its a really easy swap, it took me a long weekend to get it done and running. Hope this helps, just get a good manual and make sure you know what the wires are before you cut them. Painless can awnser alot of questions about hang up and there harness was super easy to install.