I certainly didn't come up with the idea, but I had seen some time ago a shelf that hung from the drivers side window of a Westy and supported an air conditioner. I made the same set up for my '75 Westy and it worked very well. In fact, when I sold my '75 a few weeks ago, I kept it. It will need a little tweeking to fit my '84 Westy, but not too bad. Added benefit: in a noisy campground it drowns out the jerks who want you to hear their music/conversation all night.      Jeff