So I ended up dealing with some electrical issues where my voltage would spike to 16.5 V and my Greddy EGT gauge shot up to max temp and wouldn't go back to zero.
I decided to take the thing apart and see if there was anyway of getting the dial back to zero and in the process see if the light bulbs were replaceable.
The first thing was to take the front bezel off of the cup. To do this I used a can opener to pry open the soft aluminum lip on the underside of the bezel.
Once that was off, I was able to manually move the needle back to its regular home position and test its functionality.
Boo Ya, it worked!
To get the rest of the unit apart, the two screws at the back of the case have to be removed and all the guts just fall out.
Here you can see the little light bulbs in the side of the gauge assembly.
Removing the bulbs from the PCB is quite easy as well. The large blue round plastic piece is the underside of the bulb and it can easily be rotated a small amount, counter clockwise, and pushed through with a small hex wrench.
The bulbs look like this.
And seems like they are called NEO Wedge Type 1. The bulb is 3 mm diameter and the base is 7.75 mm.
