[Chuck Glick]

As worldbringer said, our team has opened up a servo to try this and it is in fact illegal for vex competions. But if you are just doing this for fun or some other reason, what you can do is either remove the stock from the gear. The stock is what moves the potentiometer or use one of the motor gears that are identical in every way except for that stock. Another method, which we have not tried would be to remove the potentiometer completely, but this could also render the motor useless.

Hope this answered your question.