[BrianG]

OK, here's a breakdown on your options:

Option 1: Keep the two speed tranny, mech brake, and mech reverse. Of course, you'll need servos for the reverse shifter and the brake. The downside to this is that the reverse is generally pretty weak and God help you if you don't come to a full stop before you shift into reverse. And you cannot use a center diff (the diff replaces the shift fork, dog gear, and second output gear).

Option 2: Keep the two speed tranny and mech brake, but no reverse. Like above, you need a servo for the brake. But this option lets you do the FOC for a simpler, lighter, and more reliable tranny. You could also go with a center diff with this setup.

Option 3: Mod the tranny for single speed (2nd gear). You don't have to, but you can remove first gear altogether for a simpler and lighter tranny. Regardless, this is the ONLY option where you can use the brake and/or reverse using the motor. Trust me.

You are right, there is a OWB for reverse, but there is also one for first gear. How the tranny works is like this: The input shaft spins both first and second gears at the same time. But since 2nd is not engaged, it just spins freely on a regular bearing. 1st gear, being in a OWB turns the primary shaft, which turns the output shaft. When the speed gets high enough, the centrifugal clutch engages. When this happens, 2nd gear is now spinning faster than 1st gear, and since 1st gear is on a OWB, it spins freely. This OWB on first gear is what makes it so you cannot use motor reverse and/or brake.