Is the picture you posted the result of the "official" conversion Zero Wing -> Out Zone?
Interesting sub board there. The idea of a switch is cool but probably a bit out of my league
I have yet to find a high def picture of the original Zero Wing on the net where you can see the all the board clearly for ref, so if you have access to one (both sides) I'll take it
@djsheep had a Zero Wing, if he still has it he might me able to take photos for you