how do you get the brush housing off of the Magmotors in order to drill out two of the holes to mount the motors to the Team Whyachi TWM3M Gearboxes? I took off the four screws and two set screws holding in the face plate, but I'm not sure about taking off the brush housing. I don't want to just pull hard and see if it comes off, because that method normally ends up with something breaking...