Hi, Unforeseen circumstances have caused me to return to Florida and the Summer heat. The A/c is running about 12 hours a day. I have large windows on the rear of the rig. They are not double pane....
I've seen guys with the sunshade place a piece of Reflectic bubble foil between the sunshade and glass. I would think that would be a lots better than just the sunshade. I have seen this done on MH windshields also.