My 1958 has a vacumm unit in it now. I an trying to research and see the difference between the 1955,56,& 57 electric wiper units. The one that was sold to me as a genuine 1958 electric motor is different in shape to the 55-57 ones. I see a lot of adds for newly made wiper motors that will work but i would like to know if there is a difference between thr 55-57 and the 58-59 units. I found some information on it. It reads: Delco Appliance / Rochester, NY / Made in USA /
d 4903628 then a circle with 18 over 58 / 7 then another circle with the letter A in it. It looks to be a very strong unit. I am thankful for any help. Bert
