I found it was easiest to use a wire fish (coat hanger...) and go through the hood release cable area. I ran 2 signal wires through to the relays without any problems. What you use to power that--that is entirely up to you...I ran mine off of the seldom used illumination wire (...figuring if I want the fogs or lights in the back on I would at least have the running lights on). I *think* the illumination wire was blue with a red stripe, but you would want to do some searching (on this forum) before cutting into anything.
Search--"Wiring" may help...good luck with it.