I was looking for a good place to mount my EZ Pass on my 2016 Model S. There were multiple threads here about the problems with the metallic windshield on the car. On my car, there is a black painted rectangular area immediately to the right of the rear view mirror mount. I used the smaller EZ Pass issued by the New Jersey EZ Pass Authority. I mounted it with velcro (just in case) as high on the windshield and as close to the mirror mount as possible, so I couldn't see it from the outside of the car. I mounted it vertically with the narrow tapered edge to the right. It works perfectly, and looks OK, too. I am not sure how many Tesla windshields were marketed with this "sweet spot", but this solution worked for me.
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