Okay i have a 1994 gmc sierra c1500. I also have a 95 firebird formula with the lt1 4l60e combo i want to swap the lt1 in the c1500 what all would need to be done? What parts do i need? I have the parts car so i have the computer and original harness any useful information is welcomed thanks in advanced

 

Not 3rd gen related so this thread wont last long

Check out the LT1 swap sticky in the LT1/LSx forum. It covers alot of the basics not necessarily platform specific. Moving on, its externally nearly identical to a classic SBC/700R4 which you likely had start with, so drop it in with your old mounts. Both are return style fuel systems so simple adapter lines cover fuel. Upgrade the in-tank pump, figure out the exhaust and get a harness. Stand alones work great

Those are the major points

 

As long as the discussion is limited to the LT1 (which can be related to an LT1 swap in a 3rd gen) and doesn't get into details on the truck side, it can stay here.

 

The throttle body is very similar to the one in the third gens, so it would be like a 92 rs tbi. i have a cut up harness out of a 92 tbi rs that i was going to use for my lt1 swap

 

The throttle body is very similar to the one in the third gens, so it would be like a 92 rs tbi. i have a cut up harness out of a 92 tbi rs that i was going to use for my lt1 swap. You need a bracket for the trans cable that runs to the throttle on the throttle body and the right cable length. Everything else would be the same as a regular lt1 swap