There is a pretty good write up on the "other" forums. I just followed it. Be sure to practice how to solder and remove the mini LEDs before you start. There is a technique that you will find that makes removal easier. The most difficult part is desoldering and resoldering the 30 or so LED on the circuit board. Also the numbers on the faces are tinted w/ a slight orange film. An exacto blade and some sandpaper was used to scrape/sand the film to clear them out. After that just pick the color LEDs you want and you should be good to go.
I chose white because it looked very, very clean. I originally had lined the dial w/ a blue film, but I later reverted to the all white look. Note the modified redline.

I should move that back to the original 6750 since I'm not stock anymore. Anyhow, I swapped out the white needle for a red for contrast. The white needle just blended into the white background. All blue might look good, but IMO probably be hard to see at night.
Dec06_2008
White dial illumination on the speed3 instrument cluster, white needles
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White gauge cluster illumination, now with red needles
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