This is not too much solder.
As you can probably see, there are a series of magnetic reed switches that are closed sequentially, by the presence of the magnets incorporated into the fuel float. Each of the reed switches is in series with a resistor corresponding to the value of fuel level and as the magnet position closes each one in proximity, the resistance value is changed, to represent the quantity of fuel remaining in the tank.
You can make a quixk test of this system by connecting the electrical terminal of the fuel baffle and watching the fuel gauge as the baffle is rotated from upside down to right-side up, the fuel gauge should read full scale while the baffle is upside down and empty as the baffle is oriented right side up.
That is, the gauge should sweep through it's range as the magnet is moved the length of the baffle, closing the reead switches in sequence.
If your final highest resistance reading with the float resting at the bottom of the baffle is too low, the gauge needle might not reach the empty position.
It's really not all that uncommon for one of these mechanical reed switches to "stick" closed occasionally, creating an erroneous reading. I've been able to "unstick" them on most occasions simply by rapidly moving the magnetic float from the bottom to the top thus actuating each magnetic switch sequentially, through a few cycles.
Give this a try, maybe it works for you too.
