Hey, late to the game here, sorry about that. This looks great!!!! I appreciate you keeping it 6 inches or so off the tail gate in the back and not having been tempted to land right at the top. Here's something you I think will like, a lot. You could raise the back up another 4 to 6 inches creating more room under cap, and, it will lower the lift coefficient to make the truck even more stable at speed. In the winter icy driving conditions, you'll really notice the planted feel your truck will have. The higher rear panel will not affect the drag at all. These things I say are based
THIS ARTICLE. Hope this helps.