The only transmission that will be a direct bolt in is the 1937-46 truck 3 speed, with the 1940-46 being the best. 1937-39 has straight cut gears for first and reverse so they are a little noisier. The 37 trans would also need a 1938-39 front bearing retainer for the throwout bearing to ride on. (1937 was the last year for the carbon throwout bearing).
The only adapting would be to add washers/spacers between the trans and master cylinder mount as the 3 speed is narrower where the mount attaches to the side of the trans.
The 3 speed is not synchronized in first gear, only second and third.


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