Fuel Gauge Problem

At full tank the sender should show no less than 9.6 ohms. Empty is 73 to 78 ohms.
If the sender works properly 1/2 tank is 23 ohms.
Since the internal parts of the gauge have been respoding to heat created by the resistance, countless hours of toasting at full has taken its toll.
What was once a pale yellowish silk insulation on a nichrome wire winding often appears 3 or more times its original diameter. Caked with black, crunchy, nastiness. I suspect the worst examples I have seen was the result of smoking in the car. Anyway, it can't be cleaned and it does effect the needle responce.
Here's atip, If you remove the gauge , look first at the vent hole behind the top of the screen. If there is a yellowish or brwnish stain there you'll have an idea what to expect the inside to look like. Not good :(
Too much info ? Sorry just trying to shed light on why a new sender doesn't aways solve the problem. Hope this helps