FAA control room keyboard -- parallel or RS-232?

I have an FAA control room keyboard that I picked up off ebay. Each key has a little bulb underneath it that lights up the keys for use in the dark. I need to get some replacement bulbs since some of them have burned out. I haven't disassembled this thing enough to know if they have parts numbers on them or not. Does any of this sound familiar to anyone? I'm thinking that the bulbs burning out has got to be a regular occurrence and that the bulbs are therefore probably socketed and not soldered, but again I didn't disassemble it that far to know. The keyboard assembly inside is labelled MicroSwitch IIRC. -- "The Direct3D Graphics Pipeline" -- DirectX 9 draft available for download <http://www.xmission.com/~legalize/book/download/index.html> Legalize Adulthood! <http://blogs.xmission.com/legalize/>