We're coming along pretty good.
I'm slowly working on the layout and whatnot. I'm thinking it should be full LED, yes/no?
Photekq, I have some suggestions about the basic concepts.
I really think the case should support the entire back of the PCB. I am a big fan of adding a pad behind the PCB which would be impossible with your design. It really helps to absorb vibration, because there are no supports from standoffs in the middle of the matrix. Again, take the KMAC as an example, it's how they do it.
Check out this crude drawing to illustrate what I mean.
Note the screws are perpendicular to the top face, not the bottom face. Wouldn't that be a more appropriate attachment for the two halves?