[sweet70beast]

Seems to me mine are from a late 80's S-10 but bare in mind that I don't have a parking brake now. If you do go with the Caddy set up you can use ceramic pads ( no dust or noise)from the S-10 by taking of the holding brackets off of the pads, they don't list ceramic pads for the back of the Caddys but the S-10's (fronts) will work.
I had to use 79 Firebird rotors to get the 5 on 4 3/4 bolt pattern. The 79 Caddy rotors have a 5 on 5 which I think is the same as the 71 and up trucks so that rotor should go right on. I had to machine the outside of my axle flange to fit inside the hat of the rotors, I wouldn't be suprised if you had to do it with the truck axles. It only cost me $20 per side to do at a machine shop.