Get the motor rebuilt. Your scenario sounds just like the one I had on my '49 GMC. Wipers would move a bit but lock up and never really work well. I also took it apart, regreased everything and still no banana. Got a rebuilt unit and I can hardly hold the sucker from wiping across the windshield. Oh yeah, also got the dual action fuel pump. Hardly any slowness when I get the 261 going.
