electric fuel pump ?

when installing a holly fuel pump on the frame in front of the pass side tire its below the tank and using the factory fuel sending unit, which has the fuel line turned up, so the line would need to go up then down to the pump on the frame...if theses pumps like to push not pull..will that cause an issue...the sending unit also points down to the bottom of the tank, so it will still have to climb up and out.. thoughts...i know if you put fuel in the tank and dont have the line hooked fuel will run out of the sending unit...