I had the conditon you discribed with = the shaft working to the left. I tried crimping the shaft where it exits the right = side. On mine the odometer then worked for a while then quit = again.

The pot metal gear was then slipping. I = could not get my speedo needle off to take it all apart. Somehow, I can't remember = exactly, I got to the spot on the shaft where the pot metal gear = rides. Maybe(?) by pushing the shaft to the right enough to slip some wire = cutters in and put a couple small crimps in the location where the pot metal gear = rides. Then I pushed the shaft back into the pot metal gear. 3K miles and no = trouble except for noise from the speedo or cable when it's less than 15 degrees = F.