I am about to change the in tank fuel pump on my Lola T91-50 Mugen powered F3000. I was expecting just two wires into the fuel tank, but there are 5, three via the side of the filler neck, and two into the tank top plate. Anyone know why? As far as I know there's just a single high pressure pump feeding the fuel rail in there, not a low pressure lift, a swirl pot and a high pressure pump. I don't like surprises, anyone know how it's set up? Thanks.