All fuel pumps for this make ad model of vehicle are located inside the fuel tank(s). If you have one tank...you have have one pump. If you have a vehicle with two fuel tanks...then you have two. There are no external fuel pumps on this vehicle.
In a 2000 Ford Crown Victoria : There is ( 1 ) electric fuel pump INSIDE the fuel tank ( it is a vertically mounted fuel tank , behind the rear wheels and the fuel pump is mounted high on the side of the tank facing towards the rear seat )
If you have only one tank there are 2, one in the tank and a high preasure on the frame rail. Two tanks, 3 fuel pumps, one in each tank and the high presaure on the frame rail. Usually located under the cab on the drivers side, unless someone has moved it.
There are many different industries around the world that rely very heavily on fuel pumps. These industries include, but are not strictly limited to all the electricity factories in the United States and the gas industry.