Im thinking of adding some cool vintage Spyder wheels to my 72 Demon but need to find out if 15x8 with a 4.5 inch backspacing will fit in my rear wheels without rubbing on the springs or wheelwell ?. Id measure the backs myself if i could but my car is in storage and cant remove the rear wheels at the moment. Does anyone know if they will fit nicly ?. 15x6 with 4 inch backspacing on the fronts should be no problem ?, thanks Moparts.