Not easy with a DC motor, you would need to gear it down substanially, then have some kind of sensor to detect it's position (possibly as simple as a limit switch?).
This sort of application is probably more suited to a stepper or servo, depending what you are trying to do?.
I have a Futaba 4channel airplane controller and 4 servos' I bought them for $200 dollars I'll sell for $85. They are in perfect condition . email me at BriceBolse116@hotmail.com