Need help determining which hardware kit I should order..

Start by measuring the bolt pattern....for some reason they look like the 4 1/2 pattern. If it is, it's probably a '65-7 B-body rear end. They're the only one that used the 10 X 1 3/4 brakes with the big bolt pattern wheels. Good luck finding those drums! It would be cheaper and easier to just get some 10 X 2 1/2 or 11 X 2 1/2 brakes and put them on the rear end instead.