I don't know, that's why I tossed the question out there to forum participants. I installed the Class 3 Drawtite receiver hitch (the Curt was back ordered) and it was 6 bolts, a little awkward (but super easy for me using a floor jack to support it - and be sure to remove the rear splash plate or the hitch won't fit), and the harness was super easy, yes it just plugs in, too (everything from eTrailer.com, excellent company) and all at a fraction of the cost of OEM (I saved at least $500). I trimmed the removed splash plate - just cut it straight across - and put it back in for a little extra protection.
I have NOT trailered or used my bike rack yet, so I'm hoping someone who has will share their experience with respect to the rear sensors, etc.