I measured my 70 and see no problem getting a 235-60-15 to fit using 15x6.5 or 15x7 steel mopar wheels. The backspacing on the steel mopar wheels is 4.25" me thinks.

I have a b-body 8-3/4 cut down to exactly match the width of an a-body 8-1/4 axle. No leaf spring relocation, rolled fender lips or anything else.