dsam...i did this in red on my car. looks clean too. Go on ebay they have strip lights in white, red, yellow, orange, blue...etc. Flexible. Get three fit them into place. splice them into the dimmer switch, put a heavier fuse in...vualla...amber lights. None of this aquarium tubing, etc. and you can dim them too...and no hot spots if you rout the lights correctly...you want it in an arc bigger then the gauge, so it illuminates it...but doesn't shine through the holes. also ^^^ be careful not to take any needles off or tighten the screws so tight as to break the little copper wire. and the back side of the gauge has darker spots, gently sand these off to get an ever dispersion of light. mine is awesome...though during the bright day, it looks pink, and the needles don't glow.
I want someone to find out how to get the needles to glow, not just painted.
sorry for the hijack...