[Mike C]

71-72 5 lug axles are the same width as 70. The 67-69 axles are narrower. 70 is the easier conversion since you don't have to change housings. But you need to measure to make sure your truck still has the original rear.

The 71-72 will have discs in the front, which honestly, is all you need. That is the easier swap. If you do a 73 and up you need the newer truck ball joints as well. I did a 73 and newer swap on a C20 but you need to research on a C10 as it may not be the same parts.