I'm looking for the window motors. They are different for each location, left front, right front, left rear, right rear are all different. Every once in a while I get one on E Bay. I bought one a few years ago, and I just bought 2 right rear motors on E Bay. Usually the seller has no idea what they are selling. I needed some good diaphragms for my motors, and was looking for rebuildable units. Being 60 to 70 year old units, even the new ones are not useable unless they are rebuilt. When the motors are working properly, the windows zip up and down quietly and quickly. The speed can be adjusted by the solenoid valves on each end. I set mine to the quickest setting. The inch before full close, the window will slow down and close gently. There is a plunger in the window motor that purposely does this to keep the window from slamming shut. It's the coolest thing to see.
