I have a 91 Volvo Penta with a blown 305 with a 2 barrel carb . I want to re-power with a 350 vortec. I picked up a Mercruiser fuel injection set up off of a 2002 Mag 350. When I say fuel injection set up I mean I have a complete intake manifold with injectors,throttle body,tps sensor,distributor, coil, timing cover,crank sensor, wiring harness and a ecm555 computer. The only thing I don't have is the cool fuel pump and fuel lines. I am ready to order the motor and manifolds and try to put this Frankenstein together. I have found a few Merc Cool Fuel Pump setups on ebay but I am not exactly sure on how this should be set up. I am planning to have the stock Johnson raw water pump running off the crank then run the raw water to the fuel cooler then to the heat exchanger. As far as the fuel lines go, does the line from the fuel tank go to the fuel pump or to the water separator first. From what I understand Mercruiser Mag MPI have no return line to the tank but the return line runs to the water separator. Can I use the regular carb style water seperator or is there a special water separator mpi application. Looking at the Cool Fuel pumps on Ebay and looking at parts drawing it looks like the fuel pumps have a fuel inlet and outlet to the fuel rail and a return from the regulator to the water separator. The fuel rail on the intake manifold has fuel inlet and a return line fitting. That would give me 2 return lines (one from the pump and one from the fuel rail). Can anyone out there straighten me out on how the fuel lines are set up? Thanks