fuel pump

Trying to install an electric fuel pump in a '73 sedan. There is a wire coming out of the floor right where I need it, but I can't figure out what it's for. I can't find it on the diagram. it has just under 12vdc with the key on, but wouldn't spin the pump. It's a brand new pump, and spins when...

I am looking to replace the factory inline fuel pump with something like a walbro 255 and a adjustable regulator but I'm not sure what the proper factory fuel pressure. Some assistance would be greatly appreciated

I have an oil leak where the fuel pump mounts to the engine block. Is it just needing new gaskets? Is the spacer possibly warped or bad? Anyone else ever experienced this kind of oil leak? Any advice before I take the pump off would be helpful. Thanks!