See comments on your other posting.
The sending unit and your dash unit are designed to operate with 6 volts. The nominal resistance from the sending unit is approximately 30 ohms.
It is always a wise idea to fuse every appliance/accessory on the vehicle. If you have a fuse panel that is great, however an inline fuse holder is satisfactory.

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Chevradioman http://www.vccacolumbiariverregion.org/If I had known that growing old would be this much fun---I'd have done it sooner!