Be sure to shop around when buying electric/electronic gear on ebay, prices vary wildly for essentially the same gear.
Wouldn't a ribbon cable be a neater solution for power windows, speakers etc?
This was my original thought as I have about ten wires and lining up pins may prove difficult.
While your on the issue
we were trying to find a solution for nes so he didnt have to run the big commodore rubber boot to each door with all the wiring as the rear doors do not have the clerance in the door jamb
Ya killin me Pete...