You can just swap out the throttle body and save yourself a good headache by not chopping harnesses and going to drive by cable.

If you are going to do something like an 80e swap. Go ahead and do it now while you have everything apart. There are guys here that make 80e cross members, you can get your drive shaft shortened, have it repinned, and ready to go.

I had a lightly built 80e put in behind my cammed/turbo 5.3 making 554/557 and that trans was a beast and never had any issues.