[MagmaJct]

Originally Posted by franken

The ground side or positive side has nothing to do with anything. The same current flows through a circuit and the same energy is used regardless. Current flows to and from a source. Nothing is lost. Its sort of like if you walk out your front door, turn left or right and eventually walk back in. Same number of steps.
Lots of people who know nothing about electricity will give you lots of BS info. Learn Ohm's Law.

Yes, and No. You are correct, the same amount of current flows through the circuit whether the resistor is on the ground side, or the positive side of the circuit.

However, having the variable resistor (inside the gas tank) on the ground side means there is pretty much zero voltage potential at the tank. If the wire shorts at or near the tank, there will be pretty much no arc (due to the resistance at the gauge).

My `74 VW handles this very differently than our trucks. The gauge has two wires to it, one positive, and one negative. However, the positive side passes through an electrical vibrator (crude voltage or current regulator) that drops the voltage or current low enough to be safe.