BillE,
You will get many good suggestions on which way to go, you’re the one to decide; it's your Truck. Depends a lot on what you want.
The power train you pick will help point you in a direction. My direction was dictated by what I wanted, fuel injected V8,headers, 14 bolt rear and Dana 60 4x4 front.
Wheel base vs/ 54 Panel, you have to shorten a full size donor, Chevy short bed frames are closer.
The width on the donor gives you a lot of advantage, if installing a V8, steering is on outside, but you will need to make a decision with tire width, pedal, Master Cylinder location.
The 54’ frame is almost flat under the body back to front
vs/ the 80’ frame drops under the cab close to 5”. That can be a 5” body lift depending on how you approach mounting the body to the Donor frame.
Good Luck with your project
