1968 Mustang coupe six cyinder. No fuel from fuel pump

good chance the diaphram is shot. good practice to just replace it. (they dry out and rip after sitting) should start pumping relatively quickly. make sure you dont have vapor lock and your gas tank is vented. if not that thing will have a horrible time pulling fuel. the only delay really should be fuel filling up the bowls. if you dont care to cut your line between your pump and carb you could install a clear filter to see if its getting there which i assume not. the only way to prime it is to siphon gas to the pump. after that it should start pumping. again its only 20 dollars from an auto parts store and is good practice anyway.
anymore useful info would be helpful

best of luck

I would prime the engine, just take a little gas like a capfull and dump it into the carb venturi, you shouldn't need to press the gas pedal, if it helps it is okay, but the engine should start, and run until the capfull is used up (about 3-5 seconds), you might have to prime it 3 times or more. Pull your oil dipstick out and make sure it doesn't smell like gasoline. Post your results. Good luck.