I literally just finished my headlight relay upgrade yesterday! All of the advice above seems solid to me. My project used two generic 40amp 5-pin relays, and I spliced the wiring in myself. One relay for brights, one for lows.
The Haynes manual has a solid wiring diagram that helped me determine which wires to use, but you can always follow back from the back of headlights and figure it out. Mine used light green high beams and tan for low. The rhyme helped me remember which was which, too.
Also upgraded from sealed beams. May do LED in the future.
You must be registered for see images attach