Not sure what kind of wiring your lights came with. Does it have a relay and dedicated switch?
A light just needs two wires - power and ground. You could wire it to the wiring for the factory fog lights, so you can control it with your factory fog light switch. Depending on how many watts your lights are, you could splice it in directly. Otherwise, I would recommend you use a relay. The switching will be controlled by the old power wire for the factory fog lights. Then your power supply will be the battery or any decent 12V source that's only on when the key is turned to ON. I'd recommend the latter.
BTW, bumper looks great. But I just HAVE to ask... What problems did you have with the solenoid box and fairlead?