Using lower voltage bulbs
 

Have an older peterbilt truck. To get the tach and speedo to light up the same as the smaller gauges I can only find a bulb with les than 12 volts that works. Can't find a 12v with more than 3 candle power. Will this hurt anything or will the bulb just burn out. HELP

Won't hurt anything, just may shorten bulb life.
Frank