Thanks for testing with pliers.
After talking with my group, I think we're going to be using a combination of vex, erector/meccano, and a 3d printer.
The 2-Wire 393 motor has a free spin of 100 rpm, so if we gear it down 60:1 the output will be about 10 degrees per second (less, considering an added load).
This also gives it a stall torque of 885.6 in-lb, which should be enough

.
Even better is the integrated encoder module at 627.2 per revolution, or 104 ticks per degree geared.
Once we have more things figured out, I'll make sure to share.