PC Trackball controller

[Kokapetl]

I picked up a Golden Tee trackball from ebay and decided to convert it to PC using an old ball mouse. My wood working skills are limited, so I went with a pretty simple approach - The advantage being the symmetry, so that the controller can easily be rotated 180 and reconfigured as to the player's preference (buttons on the left, or buttons on the right). I haven't really played many trackball games very much so I didn't know which hand would be more comfortable for me to use (for Cabal, Missile Command, etc.) and for that reason, I really wanted to make the controller symmetrical (the reason I made the cable come out in the centre from the side).

At the moment the plug is a PS/2 connection, but I will likely be changing this to USB in the near future.
A straight rewiring is not enough for this, because the original mouse was not USB compatible. I discovered that there are 2 types of PS/2 to USB adaptors:
1. straight adaptor (just re-routes the corresponding pins), and
2. a signal adaptor (actually converts a PS/2 signal to USB)

My plan is to put the signal adaptor (which I picked up from DX) inside the box, and then have USB as the default cable. I could then always use a straight USB to PS/2 adaptor with the new converted signal if I should ever need to connect the controller to an old PC requiring a PS/2 connection (at least, I can't think of a reason why that shouldn't work).