Gearbox issues

[PAR_WIG1350]

electric screwdrivers

once you cut down the excess material (move the batteries and controls outside of the casing) they are very small. I would recommend the black & decker as-600. It runs at 130 rpm and has 2260 mNm of torque available (20 in-lbs).
The AD-600 is similar, but the casing isn't as easy to modify (on the AS-600 you simply remove a pin and the transmission can be easily removed and then all you have to do is pull the two halves of the case apart).

without the transmission, the motor in the reduced shell is about 2-2.5 inches long. You can use the transmission supplied (2-stage planetary) or you could build a custom transmission, a hex-shank flexible shaft would easily allow you to mount it almost anywhere at the cost of some power loss.