So logically, the 10 bolt is pre 77, as is my Dana 44. I just assumed it was the original match to the 14 bolt, which has a build code on the ring gear of I think 81.
I took it apart and looked again before I left, and I was thinking about this on the way home. The bearing surface is fine, its the middle of the spindle where the rust is. When I took it apart originally, I punched the races and old bearings out and took it to Napa to get the rotors turned. They had to install the new races to be able to machine the rotors. I assumed they were straight, but would bet money now one of them is crooked. Will clean it up Monday check it out. All races and bearings are new, so they should be good. Thanks for the replies fellas.