Modding a C20

[Tpo]

I know of a 61 C20 sitting on a farm not far from me. It looks pretty staright from 200 feet away and 40mph. Before I approach the owner, school me a little. Would this be a difficult truck to do the typical stuff to- lower, disc brakes, power steering? Does anyone even make drop spindles for 60-62 C20? I've searched here and found a few modded 64_66 c20s but no knee-knockers.
I guess a broader question is what are the differences between 1\2 and 3\4 ton? I believe they had a thicker frame and trailing arms, different a arms, ball joints, and tie rod ends, bigger axle and drums, and heavier springs. What else?
Thanks!