1974 Duster wheels & tire size

I want to get a set of Weld Draglites for my car. Has anyone put 15 x 10's (255/60/15) under a standard 8 1/4 rear untubbed '76 Duster?
I had Summit Weld knockoffs (15X8) with 255/60/15 on my '76 Dart Sport, don't remember the backspacing. 15X10 is too wide for a 255 tire.