Gauge prob..

I have bought a boost gauge few months ago, and it is indigo lightened( If I made a mistake in the last word, please correct it) And the problem is that it light up all the ****ing car! There is too much light.. is there any way to solve this problem?(except to buy another gauge) I was thinking to put the same thing we usually put in the window to tint them, but I only want a little piece of this, do you know a place that sell only small pieces? Or anything else I can do?

Thanks
K