Well the reason I mention an oversized panel is because they're sems to be a standard one for a few games out there. Can't think of any off the top of my head, but I know they make one...
It's the cabinet I have in my Kill Instinct machine and my brother's MK3 machine, though. I would have taken the measurements myself except my brother has them both up near Dallas.
(By the way, anybody interested in buying a KI board in a KI2 machine?)