Well, I managed to install the new fuel filter cartridge by placing the DFR in a vice (as suggested) and removing the bowl with a strap wrench. The bowl was installed quite tight and I had to use a heat gun to warm-up the fuel bowl/DFR assembly before the bowl would unscrew.

The DFR fuel filter cartridge for this truck was a FRAM Part Number CG3790 (Ford Part Number E5TZ-9365-A). Perhaps that info might be of use to someone else with the same vehicle.

Before reinstalling the DFR/fuel filter assembly, I flushed out both fuel tanks and fuel lines with several gallons of clean gasoline to remove any debris and stale fuel.

After installing the DFR with the new fuel filter cartridge, the truck started and ran but shut down again after a few minutes. It's seems the initial problem was not rectified by replacement of the DFR fuel filter cartridge so I'm back to square one.

I've swapped out the ignition module and ignition coil with other used coils and modules but it made no difference. Also, I know all the fuel pumps are operating as this was verified by jumping the fuel pump test lead to GRND.

Would anyone have any other ideas as why the engine would shut down after running for only a few minutes???