I received the case and parts today. It will indeed be a tight fit, but I think it's workable.
I think Marc will be bringing the chilluns to the beach tomorrow, so I'll go over it in person with him then. I'm much more of a visual learner than an aural learner.
This case aches for a wooden front panel, with the 1/2" recess and all. I had some 6" wide Bloodwood laying around, so that's what I used. They're in the first coat of lacquer now, and need a few notches cut into the back after finishing.
Once Marc and I agree on the internal layout I'll drill all the mounting holes and post some pics.