UPDATE: I appreciate all the comments and advice definitely gave me a lot to work from and go off of. Thanks!

It had been driving the previous two weeks after sitting for maybe two years, when I had run out of time and money working on it.

OK I see now theres not an inertia switch, but the previous owner had switched it from efi to the carburetor so I thought it might be worth checking. I also dont think there is debris in the tank as its new too.

Definitely took some of yalls advice and I actually took out the entire fuel line, pushed some mechanics wire through and then I blew through from one end to the other. There actually was only some fuel in the end of it that had been attached to the sending unit.

I also grounded my multimeter and checked the prong holes on the sending units pigtail. It would bounce back and forth between 0.00, 0.01, and 0.02 for ground. For power it bounced around from 0.00 to 8.0v. I followed the wires but didn't find their ends. Ill have to unravel the harness to find out exactly where they go, in the meantime am trying to find a wiring diagram.

Still kind of at loss as what to do next. Do I pump the gas pedal maybe until it reaches the carb? Do I need to rewire the sending unit also if its not drawing a consistent 12v? I could also pull the sending unit out and test it too.

Thanks again for the comments and advice!

UPDATE: 86 4.9L cranking issues