On my 1987 E-350 460CID Carbureator Gasoline engine with one NEW fuel pump and NEW inline fuel filter element installed in the rear 40-gallon tank I have had hard starts from sometime since I believe the fuel tank and internal fuel pump are some 25+ feet from the engine carb. I am thinking about installing a 12-volt electric auxillary fuel pump (many pumps on eBay) in the fuel line between the in-tank fuel pump and the in-line fuel filter. Would this installation impede the fuel flow from the in-tank fuel pump to the carb when it is shut down after priming or is there a bypass or is a special primer pump needed? Can you tell me the best location and how to install a 12-volt electric fuel priming pump in my 1987 E-350 460CID 4-barrel carb motorhome? THANKS!!!