I think Chuck Melton and others have done this, but can't find it on Chuck's site since there's not search function that I can find.
FWIW, Thomas Tornblom in Sweden makes a fuel gauge corrector which maps the ohm readings from the tank at various states of fill to the readings which will cause the gauge to display correctly, despite the irregular shape of the tank. Contact him directly at: Thomas.Tornblom@hax.se
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