Removing Top/Bottom Letterbox Frame

[Grindlethorn]

Has anyone been able to remove the top or bottom part of the letterbox frame so that when the slider is used in the game options only half will appear and cause the background settings of the overlaying windows to change?

I ask this because at the moment I have a UI setup like screenshot 1; in screenshot 2 the remaining black background is from the unused (afaik) MainHUD.quickbar with most elements deleted. That was then stretched behind the other windows, which all had to be clicked on in order to bring them in front of it.

Restarting the game, the quickbar was gone which would mean repeating the whole placement process. My point is, is there an easier way to do this?