Fog light question

I have a 2010 6 cyl charger. Recently I bought a new front bumper (the other was fiberglass and was crap) Anyway, the bumper (fascia) had the holes for the fog lights, so i bought some fog lights from rock auto so it would look normal. While installing I noticed that they have the wiring harnesses for the fog lights. Much to my excitement I plugged them in, but nothing happened when I turned on the headlights. I shouldn't have expected it to be that easy, but the thought was there when I saw the harness.

Now onto my question. Has anyone else been in this situation before (I assume they have). What options do I have to get the fog lights running as well? Is my only option to splice it into the headlight power, or is there a more proper way with the interior switch or something?

EDIT: Sorry for posting this to the interior discussion thread. Mod, if required please move it to the proper area.