Belt-in-tube drive base

[pribusin]

I want to propose to my team to test a new(-to-us) drive base before kickoff. It would be a 6-wheel WCD with belt-in-tube. We would use 1"x2" channel with the VEXPro bearing blocks and a single stage clamp-on gearbox with 2 CIMs. The center wheel would be direct drive with belts going from an internal pulley to the front and rear wheels. Does anyone know if that's been done before? I know teams have used chains to do this. I have two specific questions for starters:

1. in order to get two belts into a 1" x 2" channel, we would have to go to 9mm wide HTD belts. would those be adequate for the forces (driving, pushing, direction change) involved during an FRC match?

2. Could we get away with using 3/8" hex axles or should we use 1/2" hex?