I use windex on my canopies( little to no amonia) & have not experienced any problems. As far as polishing any scratches out, i have used a product you can buy at any motorcycle shop, its called NOVUS. It comes in different grades, made for doing exactly what you are looking to do. I use the red bottle first followed by the blue bottle for great results. I have seen it used on the windscreen of fullsize aircraft, and motorcycles also.....Gene