Electric wipers were an option so you should be able to find an original motor. It would mount in the same location and use the same cable type switch. 55-57 are the same, 58-59 are somewhat different and use an electrical switch. Fred
1956 3100 Pickup/Red/350/3sp OD/PS/Disc Brakes 1957 Bel Air Sport Coupe/Red/355/TH350/PS/Disc Brakes 2017 Silverado LT Single Cab SB/Black/5.3/6 Speed Trans 1947 Willys CJ2A w/F-Head engine