Looks pretty good trent. I need to learn how to tint window too in photoshop. all i know how to do is layer.
It's pretty easy. You already know how to add a layer it sounds like, well on the second layer, take a black or dark gray paintbrush and either lasso, magic wand, or just manually paint over the windows. Then when you are done painting, change the opacity of that layer. I ended up going with I think 65% opacity.