What's the optimum backspacing and offset to run for a 1978 Camaro with 15x7" up front? I'm looking at getting the Centerline Competition Series Rev wheels Also with a 275/60/15 tire, would you run a 15x8" or 15x10" wheel? Would a wider tire fit in the rear of a second gen without modifications? Also, does anyone have these wheels on a second gen (black car?) Thanks guys!