Well one thing that would help would be to know what wires you have coming from your bilge pump and or float switch. Some pumps have 3 wires coming from them and the float switch is part of the pump, and other setups have the float switch as a totally separate item from the pump. As for the breaker being connected in the negative side of the circuit, it's 6 of one or half a dozen of the other. If you were to take that setup, and cut the wire right where it connects to the battery and then take a voltage reading of the circuit, you would find that it's a + voltage no mater where you take your measurement. So is the CB really on the negative side of the circuit? It's all perception. Not being able to see how your lights are set up or knowing what your pump and float switch setup is like really does limit the ability to tell you exactly what should be hooked to where and why.