Hello! I am just wondering what pitfalls are awaiting me. I have a 1999 chevy S10 Zr2 setup, rebuilt trans and all that, but the motor sounds like Pearl Harbor. I have a 1994 Astro van that has a 4.3 Vortec, says so on the heads and has that wild looking intake on the top, and the S10 is a 4.3 Vortec it says on the plastic, but the intake is a different style. Can I take the good 1994 block, and just unbolt all the goodies off the other block and bolt them on and slap that bad boy on into the truck?

 

Can become a nightmare as the 1999 electronics will be left out. so parts wont work no more. The 1994 would need to be transplanted with his electronics.
By replacing the Trans as well you will run into troubles providing several signals to dash indications. i.e. VSS signal, temp signals etc.

that means kinda running two electronics. The 1994 would need his own power supply etc.

just some of the considerations.