I was going to make a new post till i found this thread. speedracer parts makes electroluminescent gauge faces for various cars. the faces slip right over the needle and are white. with the light on they glow blue or you can make them green, they even have reverse indiglo available.
they do not have any for opels but if we get 10 people to do a buy in, and can send them a set of gauge faces they will make the product. total kit is 50 bucks and includes ac power inverter for the faces. cheepest kit i have found.
we did a buy in on the saabcentral forums. i had as set for the saab 900 and the faces were beautiful, very clean and professionally done. the added light at night was wonderfull too. intensity of the light could be adjusted. installation literally took 30 mins and the wiring can easily be hidden. inverter is very small.
I want some of these for the opel gt like my saab 900 had. anyone else interested in a buy in? here is the link, the buy in info is under model development. here are some pics of the faces that i didn't use for the saab.