One tip that I discovered while trying to find a broken wire in the door harness was to follow the wires out of the door to the connectors at each side of the dash. (On the driver's side you have to move the fusebox out of the way to get to them.

Then use a VOM (Volt-Ohm Meter) and check the resistance (or just check for continuity) from the (now) disconnected connectors to the door lock mechanism. This makes it easy to find which wire.   Also, disconnecting a door from the control system makes it easy to identify which door is misbehaving.

Also, if you have to pull the harness out of the door, silicone spray is a great aid in getting the boot at the front of the door back in.

If you were very anal-retentive, you would run extra wires when you were repairing the original, so the next time that there was a problem, you could simply switch over to the redundant wire at each end and not have to bother with rewiring the door harness.

regards,
Todd
'88 Westy