I'm getting ready to add some relays to my headlight circuit to bypass the power from the switch. I understand the process and what is needed.

What I'm having trouble with is where the best place is to tap into the wiring. I thought that I could just find the wires needed in the engine bay but it looks to me like the wiring harness actually goes down the inside of the wing until it comes out right behind the headlight.

Any advice from those that have done this on a series 1?