[asid61]

I would highly recommend you do not cantaliever any gears. My second gearbox I designed, which we neglected to test this year under load and plopped right onto the WCD, had gear mating issues on the second stage gear because it was cantalievered.
Keep in mind this was with two bearings on it, one on the wheel block and one right next to the gear in the gearbox. The gear still had massive mating issues.
Instead, try putting the cims offset by 1/2" or so to allow for the gears to be inside the gearbox and have bearings on them on both sides.

On a side note, that's a pretty sweet gearbox. I like the way you are holding the cims with the gearbox. Seems to save a lot of space.
Keep in mind those holes will need to be a bit larger than 2.536", the OD of the cim.