Here is the original 1947 Hobart Transmission, with a bad gear. By casting numbers and the help of ebay, it appears to be the same as a 1940's plymouth car.
The input shaft has a different spline than the plymouth, hopefully it will interchange.
After years of power hopping the case couldn't handle the abuse. Conveniently there was a welder close by.
The bad gear
The second gear from the left has shelled out almost all of its teeth.
Here is my first attempt at using a electrolysis tank, after a night of soaking the rust has been completely dissolved