The gear box looks exactly like the earlier units used in the 40's and 50's. Instead of a mechanical link to the 2 speed manual lever under the dash, they put a diaphragm on it to shift the gears.
So mechanically the same, should be plenty of info on the older units.
Pretty straight forward, disassemble, clean reassemble, seal and fill.
The diaphragm is the unique part for the older units. Wouldn't be supprised if parts weren't available for 1960's trucks that used the same thing.
