I really wish I could say. When I go to get pictures from my friend I will find out for sure. I know he did have to wire it in. My guess is that is is kind of like indiglow... it requires electricity, and has a switch to change colors... hence 2 colors, or 6 colors. Now my friends sits on top of the old ones... but for my gauges, which I bet are simiilar to yours, it is easy to pull off the gauge face itself, so straight up replacing it shouldn't be hard. But of course, my tach no longer works... doh!... in pulling the needle off I messed up the spring, and no longer have one...