Gauges 1966 temp/gas part missing

Not all grounds. The new digital voltage regulator, part number 7805 is mounted on the right side on top of a heat sink (just in case!). It provides a constant 5 volts to operate the fuel and temp gauges. The original voltage regulator is mechanical (kind of looks like points) mounted inside the fuel gauge. One lead to the 7805 is 12volts in, one lead is 5 volts out to gauges, and one is ground. The capacitor keeps any voltage spikes from destroying the digital voltage regulator.

There are some threads on it here. I remember posting my pics to one and there are some articles on the web. Here's one Mopar Voltage Regulator Upgrade