First of all, good morning! At least it's morning where I am. Always nice to be working in a server farm at 2 in the am...ugh.
Anyway, unclet, thanks for that new image. That is pretty enlightening. I think I will make use of it.

I wish I had a more effective way to describe why the depth of this thing is the way it is. I'll take a picture of it and post it so you can get an idea where I'm at, at this point. However, I will be reducing the depth of it and changing the config of the buttons around the trackballs, as well as changing the orientation of the 3 and 4 player setups...thanks to your expert advice.

MikeT, I'm with ya' on the cost. I've actually been collecting parts from various sources for about six months now. I've got approximately 40 buttons, two 3" trackballs, (and a third for parts - got all three of them for $40...WOOT!), 3 spinners, (an original 'Tempest' spinner and what is apparently a 'Mad Planets' spinner), somewhere in the neighborhood of 12 joysticks, (no kidding - I bought a 'lot' of parts on evilBay and wound up with a whole gaggle o' functional joysticks), two mini-pacs...and on and on...
Considering that I'm not very good at the carpentry aspect, (as I've babbled on endlessly about on the 'Everything Else' board

), I'm reluctant to try and build the raised pieces. It did occur to me though.
As for the buttons above the joysticks, those were originally supposed to signify the 1-4 start buttons and coin buttons. I think with unclet's help I've changed my mind about that piece.
Thanks again for all the help and advice so far!
Lharles