I think your wiring is right for a 12V system (you say yours is 6V though) and the wire coming off the starter solenoid is the resistor bypass wire. Since you don't have a resistor it seems to me the wire going to the starter solenoid is useless. I would take that wire off the solenoid and eliminate it leaving you with just the one wire from your ignition switch to the + side of the coil.
