Help! Fuel gauge

This was the exact gauge I got and it read 1/4 tank when empty with the stock sender and the correct ohm rating, even though the original gauge was accurate with the stock and working sender.
I replaced the sender with a new one and it got pretty close to accurate.
At about 2 needle widths above the empty mark is actually empty now.

That's why I say it's kind of a crap shoot.

Thanks Guys! That at least gives me a starting point on the 10-73 ohm range. I know what to look for now.