Well what I would do is look into what it cost to get all the parts and steel together to build a roll back, look at a few and take pictures so you get an idea of how it works and a plan as to how to make it.
Then I would look into buying an old roll back, the idea is pull the roll back off the truck you buy and mount it on your 65 c60. I think it would be cheaper and better to find an old roll back and mount it on your truck, than build one from scratch. and fix up the cab and chassis amd sell that to cover expences.
jbennett
40 burb