Chevrolet 3100 pick up -49 original front + rear end?

[Dundee]

Could someone say whether those front and rear original?
The rear end would probably not have a lock?
The purpose will be to put a mustang 2 front and rear 4-link, do you think the big thing?
I was going to buy the parts of the No Limit movement, or would it be something like one of the better places available?
I had a bit of a hurry with it, so thank you very much for your answers!!!