Before reading the back story:
It is a dilemma. Fixing motors and drive train, new wiring, glass, springs, patches will still be the same truck. New cab and take off dump bed. Not the same truck. A new cab will change the VIN. It all boils down to the price of sentimental value.
After reading the back story:
The page no longer has more pics. So can't advise how to proceed. Can't assess the rust. As a guess, the idea of buying a donor truck may be the best and cheapest idea. I am pretty sure you can find one with low mileage and low use. Which means a good body, good springs, good glass, good rims and etc . All in one purchase. You do live in snow country, which has rust galore. However, many of those trucks were in a shed or under a cover and never traveled salty roads. Find one. Take your time for the right one. Then you will decide and design the way to "restore" the truck. Swapping and repairing. You MUST do the patching and welding yourself. It has to be easier on a big truck than the pick ups. Better access, higher up work angles. After you do a patch or two, you will get the hang of it. You will be good at it. It's not that hard. Having two trucks side by side while repairing is a great advantage and will save a lot of time. Just prepare a good work area with dry ground, electricity, chairs, tools...
"I am not confident with body work and don't really have the desire to get good at it." Change this attitude or don't bother. You have Stovebolt to help you at every step. I don't do "body work" either, but I sure have done a lot of patch panels, weld, grind, skim bondo......a little dent repair. Not the hours of sanding, primer, sand, primer, sand, primer stuff. You don't need to do that either.
EDIT: Was still typing, then saw the post above mine. Bottom line is crenwelge, HRL and I are saying the same thing.
