Gas Gauge not working

[Stang Guy]

So I have been trying to fix the issue of my gas gauge not working over the past few months when I have free time. I've replaced the fuel sending unit, the ground wire from the sending unit to the frame, the wire from the fuel sender to the fuse box and the fuel gauge itself. I also replaced the circuit board behind the gauges also and the fuel gauge still does not work at all.

Has anyone else experienced this issue?

The one thing that seemed odd to me is that the wire from the fuel sending unit "plugs" into the front of the fusebox. Is that correct and which place is it supposed to plug into? I am wondering if it was connected in the wrong place.

Thanks for any help in diagnosing this issue!