Correct! I did the same thing. Bought the factory tow hitch and wiring harness; wired it up; had the dealer 'activate' the harness, and it works as intended now.
You will have to cut a notch in your rear bumper to have the factory look, though. But in my opinion, it looks much nicer than having the hitch below the bumper.
2007 WK - Silver WK Club Member #71, 4.7L V8, 5 spd Auto, Autobot Decal (grfxedge.com), Aspen Creek Front Tow Shackles, Factory Tow Hitch
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