BubbaJoeXX:

Look to be standard Tamiya DMD gearboxes, the ones on the right with the tab in the opening seem to be Type Two gearboxes (first black-cover'd ones) I blew the pics up, could see that annoying plastic gear (someone have the repair/replacement gear packet #?) They should fit fine inside a Sherman (and motors sit even lower with the 3:1 reductions)

You can apparently adjust the ratio on the new boxes ( on the left) manually by removing the cases and adjusting the spacers on the gear-shafts, or so I think I remember reading on ArmorHut a while back. You may still want some 2:1 reducers on 'em...

I gotta salvage more soda bottles to make covers for my Type 1's w/ their now-rare HPC gear-sets. Even have a Wroe reduction assy laying about I think.