I have the WV rallyes on my 73 RR. 15x8, 4.5 backspace with 275/60s on the rear. Fits well. 15x6 on the front with 205/70s on the front. Can't remember the offset. Going with 215/70s for the front next time. The 73 RR has a large front fender opening and I think a taller tire will look better.