Synchromesh is greatly improved. The later gears can be installed in the early cases, but the '39 forks must be used. Do not try to modify the earlier forks".
Modifying forks was pretty common and reasonably useful years ago, but the second-hi fork used a different coaxial offset for the later synchro which was fixed by drilling a new rivet hole in the right place on the shift rail. Grinding the fork to the 3" spread completed the fit. Such mod is beyond todays needs with the access to the superior late 81, double detent tops with the right fork being available.
"You can use your '36 motor mounts with the later cases, but the '37 & later mounts offer more stability. For this conversion, you'll need to weld the later frame mounts, and modify the later ****** mount to accept the hand brake.[/Quote'
Seems like a lot of work for little to no improvement over the '36 rear retainer and mount. Fred A
"all I did was use the 36 trans baring retainer and 36 rear mount. everything bolted right up. the only thing I had to change was the arm for the clutch