Gas gauge calibration unit

Here are some calculations I made in a calc sheet. I do things like this prior to writing code.

The current source measurement of sender is linear compared to the gauge resistance in conjunction with sender. Not sure the linearity of the sender and gauge. I have always noticed that fuel gauges seem to be slow to move off full, and fast near empty. If using the current source is not an improvement, the use of a 20 Ohm resistor to feed sensor, and a few changes in measurement will fix that.