i have a 2011 ford f150 want to install automatic lights on/off. i tested the system and its postive switch. do i conncet the wires from the unit to the neg wire at the switch or to the neg wires at the headlights it shows 1 green wire to lower-beam headlight relay 1 purple wire to licence plate lights 1 wire 1 yellow wire to left headlight 1 blue wire to right headlight . also it shows one wire on the unit that goes to the (+12v) main beam headflight input where is that. thanks