I'm running 15" Cragar SS with 7" on the front & 8" on rear on my 68" Tires are 215/65's. Car is stock height. 4" backspacing on fronts, not sure about rears...it's either 4 or 4 1/2. Back has plenty of clearance. Fronts would rub while cornering if I tried to lower front end by over 1/2 in. Front brakes are SSBC single caliper discs. Back are factory drums.
