I bought a 1959 one ton panel a week ago with a late model rear end, probably a 3/4 ton (I saved the truck just before it was hot rodded). The truck only has 9,200 miles on it and the original rear end had been removed for a few years and sitting outside. I want to put the original rear end back in the truck (putting it all back original), however I was surprised to see the differential cover was rusted with several dozen pencil lead sized holes. The inside has surface rust on everything. Is there someone out there who rebuilds late 50s one ton rear ends? Can any local shop do it? Should I just stick with the late model 3/4 ton rear end that's in there? Any thoughts and/or suggestions would be welcome.