[Guest]

I think that’s not possible, no reflection at all, they are indeed just alpha channels (transparent) of the textures. You can make it lees transparent or in some color, but usually looks even more silly.
Here is file for Hurricane for example, which one we see as “canopy reflection” so you can get that “blur” darker or in another color (like on hellcats), but that’s it. It looks like very oddly stained glass. As far as I have researched.

Also, little more filthier perspex would look cool, but . . .