[700rpm]

Neal, I would suspect both the 7-tooth box and the rubber ball. I had both of these situations on my '29 Tudor; getting rid of the rubber ball helped, but did not solve, the problem. My local Model A expert said the steering box needed to be rebuilt and adjusted and I needed to replace that wishbone with one that had a good ball. In the meantime, before I get to all that, I have installed one of the hydraulic anti-shimmy devices on the front axle, and that seems so have relieved the problem until I can get to the major stuff.