I'd fix it, and have done that with most of the vehicles I've ever had.
In the old days- any car or truck I got had:
1.A blown engine.
2. Over a hundred gazillion miles on it.
3. needed a paint job.
4. was wrecked.
Always two, but sometimes three of the four.
I'd restore them as I went along, and kept most of them for another 10 years.
On yours, I'd get it safe and mechanically sound first, then do the body shell stuff last.
Cost wise- look at how many car payments it would take to cover what needs fixing
compared to how much longer it will go without the same car payment expense after you've fixed something.
Just being a standard trans. is worth a lot now days.
I have found that with the 6 speed manual in the F250----- nobody wants to borrow it.