[EricH]

FP gearbox: If it's a large black monster like I think it is, you cut some nice solid stock (wood or metal, metal preferred) into a hexagon the size of the inside of the output. Use a hose clamp to lock the teeth around the hexagon. You'll probably want an axle hole in the center of the hexagon.

Now, you make your winch and attach the winch to the hexagon. How this is done is left as an exercise for your team. There are resources on CD and in other places.

If you're really savvy, you can figure out how to use a servo or pneumatic cylinder to act as a locking pin so you can stay in any given position for as long as you need to (i.e., go there, lock, unlock before moving).