Yes that shifter arm will work. The end of the arm gets worn and it gets sloppy, but keep in mind it is not tight like late model transmissions from the factory. You can remove the top loader after removing the center portion of your floor, it will be a direct swap ,no issues. Just make sure it is neutral before you pull the cover, The only diference between the early torque tube sm420s and the post 55 ones is the rear bearing housing and yoke/ujoint.

Granny is non syncho, but all post 48 trans have the synchro 2,3,4

Last edited by sstock; 04/11/2018 1:21 AM.
1953 Chevrolet 3100
261 cu inch, sm420, 3.55 rear, torque tube still,omaha orange, still 6 volt, RPO green glass, side carrier spare, all done
In the DITY Gallery
Video of the 261 running

1964 GMC 1000
305 Big Block V6, sm420, the next cab off restoration