Flat can with a long shaft.
I applied to the Yahoo group you mentioned. The worm is mounted on the motor shaft (slip fit with set screw) and goes directly to the axle gear. I had cleaned and lubed the entire model. It was imported in 1957 and looks like it was never run at all. The worm gear still had over spray from when it was painted. I would be interested in tuning it up instead of replacing it.
Thanks a bunch.