Thanks, Harold41, for the shaft tip! I'll check it out. I'll check my '46 and see if the grommets are still there and let you know if I find anything.
If nobody on the board can steer you regarding the proper hookup of the wiper arm, try "TheWiperMan", Fricken vacuum wiper repair. He may be able to tell you about the hookup. I was thinking of sending my motor to him until I got that nut off. He's got a website and I think it's called "Thewiperman". Let us know what happens. Jacques
