OHC display
 

Has anyone ever changed the display color to something other then blue or green? Is the color just determined by the lens? Are there LED's that can be changed?

I highly doubt the LED's (if they're even LED) can be changed. Have you ever taken apart an OHC? I have... I've never lit one up without the green or teal filter to see what color it lights up. If it's white, you could use some glass paint on some plexiglass to make a new filter.

I haven't taken one apart yet. (it should be in the mail) and if they are LEDs I'm sure they can be changed with the right tools and know how.

ive taken mine apart twice and its not leds im pretty sure, since that technology wasnt that prevalent in the late 90's

no, they are not LEDs. The display is a flourescent display. The "raw" color is probably close to blue, but can be made to appear green through filtering.