94 305 tbi to 97 350 Vortec swap

Well George this is kind of a trick question and depends on what you are hoping to do.

1st: the computer system from 94 is OBD1 and computer system for 97 is OBD2, so the old system will not talk to the new one, I am also thinking the plugs for wire harness are different because of this reason, so if you are thinking of using fuel injection and all engine controls from 97 with 94 truck it won’t work. I guess you could try to install 97 harness and computer in 94.

2nd if you’re thinking of pulling intake off 97 and swapping on the 94 to address item, this will not work either because they changed intake and head bolt pattern between 94 and 97.

3rd I think distributors are different between them as because of computer and camshaft style roller in 97 and flat tapped in 94 so dist gear is different.

this swap is do able but you would most likely convert the engine to a carb with a new vortex style carb intake and an old school HEI dist. Then there’s the problem of the transmission shift control. I know nothing about how to work around this.
These are some of the things that come to me as I think about doing this swap, I am sure there is a lot more then I can think of.