I'm not sure I'd agree with this. They should fit fine in the back. In the front a 14 x 7" wheel might hit the tie rod ends or the end of the upper control arm but the 15" diameter wheel, because of the larger diameter, should give enough room to squeak by. I ran a 14 x 7" wheel with 4 3/8" back spacing on the front of a '64 Barracuda by using a 7/16" spacer with stock 9" brakes. The same wheel worked fine in the back, both with the stock 7 1/4" rear & later with a stock A body 8 3/4" rear.
