I've been dealing with a fuel gauge issue as well. What you need to determine from the start is, is the gauge good. One shot of 12 volts to an original 6 volt gauge will fry it, I bought a voltage reducer for my truck plus a replacement gauge since the original was fried but after inspection of the sender I see that it too needs to be replaced.

Let me know how you make out,
Rick

1951 Chevy 3600, 1996 Yukon, 2000 Road King
It is easy to take liberty for granted, when you have never had it taken from you.
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