71 Duster 318 fuel pump not pulling fuel from new gas tank

Possible the check valves in the pump have dirt in them. I would try hand priming the carb, depending on carb. If it has an accessible vent, use a syringe/ bulb, etc to squirt some fuel into the vent. You can fill the bowl, and engine should run, probably on just one fill, long enough to prime the pump. You have one of those hand pump vacuum testers? You can pull a vacuum on the fuel line disconnected at the carb.

Or just throw about a tablespoon of fuel down the carb throat and fire for the few seconds it will run. I would not think you'd have to repeat that more than 2-3 times

You should NOT have to do either. A clear/ clean fuel delivery line and a good working pump should prime. It might take some cranking.

Also, are you certain the connecting hoses, at the tank, line to pump, etc, are not crimped/ soft/ collapsing?

Are you sure there are no line leaks, loose clamps, mis-sized hose to line, etc?