If you saw my Project Announcement thread (don't have time to look for it right now), I planned on initially creating two panels - one with just joysticks and the other with two trackballs but only three buttons (space limitations).
However, after thinking about it, I realized that visitors (party, for example) may not be inclined to switch an entire panel to play a simple trackball (or, in a pinch, spinner) game - though they may want to considering the cab is designed after Centipede. Also, I hated the idea of whipping out the two ball panel for single player games.
Basically, I'm simplifying things a bit. I'll still make a dual-trackball panel down the road - but only for those rare two-player TB games.
I'm incorporating a 3" trackball into the main joystick panel. Here is the layout with and without graphics (the CPO need clean-up and I may work the border around the TB - otherwise, forgive the crudity)...


The panel size is 25" wide by about 10-1/4 inches deep. As you can see, I'm going to have to install the TB without the mounting plate (which is just going to be a heck of a lot of routing). The joysticks are U360s, by the way.
I plan on doing a cardboard mock-up this weekend - and a dry run on wood should I have time and confidence. In the meantime, anyone see any problems or concerns with this layout -- or have additional input?