Couldn't find the camera last night, so no new pics, but a little more information... The sides are, in fact, green laminate. The control panel is hinged at the bottom. Removed part of the Birdie King II CPO to reveal... Another Birdie King II CPO. Coin door is a generic type over/under door, not Bally/Midway.
Marquee seems to be made to fit the cabinet, which is strange because it's an abnormal size - smallish.
Control panel seems to be bolted on with carriage bolts, rather than clamped on. Will see about taking it off after work today to see if the holes for the start buttons/trackball are the originals. Hopefully this will reveal something interesting, but I'm not holding my breath. May be a lost cause trying to figure this one out.
Control panel shape, coin door, profile and marquee are all wrong for Sarge. Given the control panel (shape and cone buttons), I'd say this is almost assuredly some kind of Atari cabinet. I also went through the list at KLOV, but there are a lot of cabinets with no pictures there. No telling...