Exactly.
The only difference when I did it on my Superduty was I installed a fuse between the hot terminal I used as a source to both the high and low relays. I wired the control wiring to the original headlight plug, soldering the wires to the filament holder wires of an burnt out bulb and plugged that into the headlight plug. If I ever wanted to, I could go back to the stock wiring (but why???) simply by unplugging the relay harnesses and reconnecting the headlight plugs back to the bulbs. I also soldered a diode into another old bulb and plugged that into the unused socket so that in high beam, the low beam relay was also activated (both filaments on at once).