You should simplify and buy the #MX01132 pre-made headlight wiring harness (with relays) from Classic Industries.
A few weeks ago a similar thread (regarding HID headlights and upgraded wiring) was going around. Have a look as it will provide some added info. Attached is a photo of the post that I made on that tread ... including info on the pre-made harness with relays.
http://67-72chevytrucks.com/vboard/s...d.php?t=419322