just the motor and switch is all you need. wiring is fairly simple as the motor is just two wires. make sure you get the switch that has i think it is 4 or 6 terminals . the older style chrome toggle style switch (looks the same as they used in the GM cars) are the ones i used and they can be found in the mid 80's mustangs as that is where i got mine out of. the newer switches uses remote relays to reverse the motors, while the old switches just reverse polarity in the switch to reverse the motor.

you can get the whole door if it is easier to remove and that way you can see how the wiring is, but you won't need anything but the motor and switch in the end (although the wiring harness would be nice).

goof luck
Mike