1972 custom 10?

[coggonobrien]

hey guys, i've got the opportunity to buy what i am told was a 1972 c10 shortbox frame. Whats got me confused is i saw the front clip off of it and it was the 71/72 style grill but it had custom 10 badges on the fenders. Was the custom 10 package around in 72? I saw the frame and it is a shortbox, 2wd, front disc, trailing arm/coil rear, 12 bolt complete with wheels (steelies). Also what is my max 15" rim width/backspacing with this combo in a fleet side? Btw i paid $200 for the thing.

Thanks!
David