Not a whole lot to add...
Your wires will be brown with yellow stripe and red with black stripe. If they are not in the door at all, they should still be on the car side of the doors harness connector. You should be able to find them in the bundle that enters the car right above the fuse box. You would then have to run wires from the door side harness connector (assuming that they aren't there). Not an easy job.
I couldn't find a pinout for the door connector, so you'd have to probe to find the correct pins.
You can see the wires on the left side of this picture.
