4.3 TBI to 5.7 TBI Swap Questions

[Greenlee]

I used the wiring harness from an 89’ Suburban when I rebuilt my truck. I’m intimidated by wiring also, but it really wasn’t that hard. Everything is plug and play. Each system, including the dual tanks, have their own separate harness. It’s just tedious work getting all of the wiring out without breaking anything. Once you get it all out, you will have the fuse box and a bunch of separate harnesses for lights, windows etc that all plug into the fuse box. You will need the computer from the Suburban. The computer itself might be the same, but there is a different chip that plugs in for the 4.3 vs. 5.7. I have an old build thread on here somewhere from when I did my truck.