Identify front and rear end?

[M1A1TankerTom]

Hey guys, I have a 62 chevy short bed fleetside pickup. The front end had been swapped to a later model chevy pickup for disk brakes. The rear end has also been swapped out of the same later model chevy pickup. It now has a 5 lug pattern. The only thing is that I have no idea what year truck the new front and rear end came out of? Is there any way to identify what year they are?

I talked to they guy that originally did the swap and he said that he thinks it came out of a 70's something truck but he is not sure at all. Any help or ideas would be appreciated.