Hi! you have a returnless fuel system, with a regulator that is built into your fuel pump.
When you replace the pump, you will be replacing the regulator as well. Only way
to get it is as a complete unit. You are correct, the regulator most likely failed,
especially if you can hear the pump run, but the regulator is located in the entire fuel
pump assembly, and if you have not studied this specific system, it is hard to know.
Thanks
Nick.
Hope I answered your question, an accept, and bonus is always appreciated!
Nick
ASE Certified Technician
Ford Drivetrain and Chassis Master, ASE Master Technician