Help! Fuel gauge

http://www.autozone.com/gauges-and-...-level-gauge-for-ford-and-chrysler/39165_0_0/


I have one of these was fitted when I bought the car seams to work fine ( I've sanded and painted the aluminum flat black looks way better )

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.