I remember someone writing a guide with pictures and part numbers for this, however I can't seem to find it now...
You have to take the dials out of the dash,and replace the orange leds with blue or white, whichever you prefer really...
The LEDS are little SMT ones, so you just need to be good with a soldering iron, especially when removing the old ones, so that you dont burn the tracks off, otherwise I think its expensive to buy new dials....
Hope it helps, and try a search for the guide....