Ihave a 65 220 rambler and mounted a ford 8inch from a mavric i belive it 53 inches from back plate to back plate it mounted nicely just had to move spring preches the wipers any newer moters will mount just have to get wire harnes mine had vac and changed that to i know it hard to find parts for these thing i need a rear window but theres a place in ill or ind that took over ed stack in cali inventory hope i was some help i grew up on amc