To wrap up the saga of the right foot motor repair on droid #2, the JB Weld had fully cured, so I tested the motor with a spare 12 volt battery.
That blurry gear is the result of the motor humming along happily at 285 RPM. I now think the repair is going to work out, but time will tell.
The battery box is almost perfectly flush with the foot shell now, but I may fiddle with the fit a little more to make it perfect. Or if I'm smart, I won't. But lately I haven't been too smart.