That'll be a good project. Are you doing a 27" LCD or a 27" tube monitor.
I'd think an LCD is the way to go for something like this, otherwise Javery's right, it'll be a huge cab.
I too think you could likely do better than that cab. Put some cabinet panels on the sides, so trim, something along those lines.
Heck maybe even grab a tambour and make it a rolltop arcade cab!
Good luck!