Remove the door mounted speaker & the upholstery panel to gain access to the motor. There are 3 screws (5/16" hex head, I think) that secure the motor in place. Remove them and the motor comes out without any problems. Once you remove all the screws from the motor, and it falls away from the gear teeth on the arm for the glass, the glass will move up and down. You may need a helper to hold the glass once the motor screws are out, since the gear on the motor holds the glass from sliding up or down
The motor is the same for left side or right side, only the gearboxes are different. If you can't find the complete assembly for the side you want, you can get either side and use the old gearbox on the new motor.