The only simple method to have 1 pump instead of two for that engine, is to use a carbureted engine instead of a fuel-injected engine. In fact, that's how Ford first designed the 2.8l Cologne V6.
When they changed it to a fuel-injected design, they needed more fuel pressure at the engine. Rather than redesign the fuel delivery system entirely, they instead added an in-line "booster pump" under the cab. However, this design is reliant on the original "lift pump" in the tank. The booster pump cannot draw fuel out of the tank by itself, reliably, and the lift pump cannot generate enough fuel pressure to run the engine.
Later designs changed to use a powerful enough pump in the tank to pressurize the fuel system, but they also increased the pressure specification for the fuel system almost double, and eliminated the 2.9l engine design as an option. If you put one of those pumps in your tank, it would do a whole lot of work to push a whole lot of fuel, most of which would get returned to the tank by the pressure regulator.
If you looked up the flow rate and pressure rating of your current pump system, and found an in-tank pump with similar numbers that is also the same length and mounting as your current pump, that should serve your purpose. You will also have to install a check-valve in the fuel line where the booster pump was located, because the booster pump includes a check-valve internally. Without the check-valve, you will have to crank your engine significant longer before it will start.