I swapped my C60 with a Dana 70. I do not plan on hauling anything crazy which is why I went with the 70. Honestly, I kind of wish I went with something larger, and more heavy duty, but that could be done fairly easily in the future. Take a look at my build thread.
https://www.stovebolt.com/ubbthread...05857/1958-viking-build.html#Post1305857Swapping was very easy if you have a good angle gauge, flat ground, frame stands, and a welder.
Also, it is not a two speed, obviously. Just thought I would chime in!!