Any thoughts on how difficult it would be to swap the 350 TBI and 700r from my rusty 1989 GMC Vandura into a 1988 Chevy Silverado? Would that combo mate up with the transfer case? Would I just keep the exhaust headers from the van's 350?

I ask because this van is rusted out fairly badly, and I've found a nice old OBS 1500 with a 305 that would be a good fit for my motor and transmission.

 

I am pretty sure that will work for you.

 

They should bolt in place fairly easily but you’ll probably have to keep the exhaust manifolds currently on the truck and possibly extend or shorten the pipes to accommodate.

You may also need to have the rear driveshaft replaced or modified depending on where the rear of the TC ends up.

Compare the computer controls for them as well - if the van has components that the truck doesn’t, use the computer and wiring harness for the van.

 

Thank you guys for your help. When people say the 5.7 will fit, does this mean the motor mounts are the same and wouldn't require any fabrication?

 

Correct. The 350/305 are both small blocks so the position of the mounts should be the same. These blocks also have additional thread bungs on the sides which make it easy to make slight changes to the position if needed. You won’t know for sure until you attempt to install it.

In addition to the manifolds and driveshaft, I think you may also have to work out front end clearance for the radiator fan/shroud - but again, you’ll have to see when you get it installed.

I wouldn’t expect too much hassle as a result of the swap, though.