I have the 280mm sender unit, complete with Richard Woods shunt resistor fitted and to be honest it made little difference to the contents readings, they were still pretty random. The thing that did make a difference was to remove the sender unit, take off the metal cover tube and clean the two thin wires with some fine abrasive paper. After that the readings are fairly stable and the contents indicates a steady(ish) fall down to 0% over about 200 miles. I think that is about as good as it gets with this system. My recommendation is to clean the corrosion from the two fine wires inside the sender unit.
