Like someone mentioned above pactra pants made to paint lexan bodies of R/C cars/trucks. Not only do they make transparent and candy colors they make actual "tint" that's used to simulate window tint and that is what I use. Spray it on the inside (mask the outside first) but remember - by the time you look at it and you think it's dark enough - youv'e got it too dark because off the plane the canopy is backlit and it will take a lot of tint to appear tinted. However, when you stick it on the plane with no light behind it - it will appear as black paint. So my advice is to a few thin coats and place it on the plane or something solid to eyeball and see what it looks like before you get it too dark.