If you've got one post a pic of the back side as well.
Well, my setup isn't exactly what the guys have described here. I did use the aluminum bezel sold here to house the gauges, but the back side is a gutted factory cluster housing with part of the printed circuit still used. I did that because I wanted to use the little turn signal areas with the arrows, and the bulb housings were practically impossible to just solder connections on to or something. Now in hindsight, it would have been much easier to just use some little green LED's from an auto parts store.
You have several easy options for the accessory lights, you can buy LED's in green, blue, and red. I used a blue one for the high beam indicator. Several of the other option lights I've ditched altogether.
Most of my wiring is direct to the fuse block. I rebuilt my entire wire harness and did this project during the rebuild.
The wires are pretty simple actually. LOTS of them for bulb power (very low amp draw) and then I branched a bus connection for all the power for the gauges individually. Ground is obviously, a piece of cake. Other than that, its just the connections for all the sender wires.
This was where I soldered wires right onto the printed circuit. Again, pretty silly in the long run when you can simply buy some LED's, although this was as cheap as cheap gets!