I didnt have to do any factory wire cutting or splicing which was nice. The high beam wire for the instrument panel is a bullet type connector that Y's into the highbeam. I used a bullet connector on the high beam wire from the dimmer and plugged it directly into the spot were i pulled out the high beam wire from the instrument panel and i did the same for the toggle switch on the low beam for the HID install.
Next i made a wiring harness with a 5amp fuse and ran it to a toggle on the dash then to the dimmer so i can cut all power to it if i need to. The switch is a bit overkill but is weatherproof and was cheap! A bit over $6.00