Perhaps I missed it in all the Tribute discussions, but what's the purpose of the removable cover - is that for someplace where Jerry...uh....hid...a certain something?
 
EffClef

Stash box!  I would think in a forum of this nature, it's not 'taboo' to discuss it.  I thought I had read that either Phil Lesh or Jack Casady had something along those lines as well, but I could be wrong about that.  Definitely a cool feature, if it exists.