Get a couple small metal hinges, and drill holes through the top screens sides right under the speakers, and put a clip on the Guitar and at the top of the top screen so it keeps the screen closed.
Would be a lot easier than relocating the top screen, or doing without.
Metal hinges might look weird, and to be honest, I'd rather not have a screen sticking out of it. For the amount of time I'm going to be looking at the screens, I think one screen, put inside the guitar with a hole on the front, will be fine.
But of course, I still can't find a cheap enough DS... I wish I wasn't so cheap!
EDIT: Got the DS. $42 shipped... I hope it was worth it.
If you're looking at this post and it was made before 2008, just ignore it.