I have a manual bilge pump with a two way, on/off switch. I bought an automatic Rule mate 500 pump with the internal float switch. I want to hook it up without having to install a three way switch. Now, if I hook up the wires for the manual circuit to the existing switch and hook the wire for the automatic circuit straight to the battery with a fuse, would that work? Would I be able to use the manual circuit if for some reason I needed to?