If you just want white gauges and don't care about an increased max speed calibration on the gauges (honestly, 160 is fast enough) then I would HIGHLY recommend just buying a set of SLK 320 gauges from ebay. Buy the ones from 2001+ as the finish is a crisper white than pre 2001. See attached photo below, the top one is the style you want.

Also, refer to MMZ_Timelord's gauge color thread... instead of fooling with the paint sanding step, simply install the white SLK overlay in place of your OEM black one, and VOILA!!! You have white gauges, a functioning fuel gauge, and you retain *exact* mileage.

If I had another N/A this would be my first mod, as it looked brilliant.