[Mike C]

Nice truck.

Yes, you can use a donor newer truck setup. You will need all of the brake and steering parts. The disc brake trucks ball joints and tie rod ends are different than the drum brake parts. You might save a few bucks. Or not. You will do much more work and it will take a lot longer.

I did the ECE converison on my 69 short step. I did the 2 1/2" drop spindles along with a 2" drop spring.

It is possible to get the pin out of the differential but it is a pain in the butt. It really needs to be fixed IMO regardless of what you do. And there is no way to correctly redrill the axles without removing them from the truck.

If it was mine, I would buy the ECE conversion setup and I would find a used 5 lug axle assembly. And actually, that is exactly what I did on my truck. Mine is a leaf spring truck and I found a 5 lug leaf setup on Craigslist that I swapped my original limited slip into.