DDR,
Sorry to tell you but your illustrator file is off. The height for one is NOT 21.5" but rather 22".
I'm and EXPERT in Illustrator. I've used it professionally nearly everyday for the last 18 years...
I took the liberty of rebuilding your file. See attached. fixed the alignment of both the monitor cutout and both inner and outer dimensions as indicated and cleaned up the artwork including the artifacts around Ms Pac-Man. Resized and moved a couple of other graphics including Pac-Man, which was not centered.
I'd strongly suggest using my file even if you decide to move the graphics around to your own liking.
[EDIT: my zip file won't load. It's 2.2 mgs. Send me a private message with your email and I'll send it to you]
See here for other arcade/character artwork I created for my own cabinet.
You're welcome to use any of it if you'd like (vector format for Illustrator):
http://forum.arcadecontrols.com/index.php/topic,123292.0.html