[MPtyza]

Red goes to power, black to ground (I'm sure you probably knew that already though). The two pronged one is for the on/off switch. If you don't have the one it comes with, you can just bridge the two prongs for a second with a flat blade screwdriver and they should come on. Bridge them again for a second, and they turn off.

It looks similar to the gauges I put in my girlfriend's Impreza a while back, and that's how those ones worked, so you may have some success with that.