, 98+ Rangers are returnless fuel, meaning that there is a single fuel line up to the fuel rail and no return line back to the tank. With the returnless system, the pressure regulation is done in the tank.
The return type system used in earlier years regulates pressure at the fuel rail by dumping the excess back to the tank through the second fuel line (return line).
If there is a single fuel line to the engine, then the device on the rail is not the fuel pressure regulator. There a fuel pulse damper on the fuel rail of the returnless trucks that looks very much like the fuel pressure regulator used on the return fuel trucks.