[LoJac963]

The easiest way to go about that is using relays for the lights. Even though LED's don't pull much voltage/amps I would feel better myself using relays. That way the signal wire for the rear (reverse lights) would be simply that, a signal wire to close the relay. That would hold true for the front using a signal wire off the highs.

That would not be difficult by any means. Adding a switch shouldn't be a problem either. You would have an accessory and ground powering the switch, the signal wire from the switch would go to the same relay to close the relay when the switch is activated. Basically you'd have 2 signal wires going to the relay as opposed to just one.

Hopefully that isn't too confusing. I could make a drawing but believe me you'd be better off without me drawing something