I have time now
Had one mounted by a local trailer hitch place. I was wondering about a Mercedes but they had pictures of their work and had some of Mercedes and even Roles Royce. I didn't actually see them do the work but I know they took the bumber off and all the plastic trunk lining stuff out to install it. They welded a cross piece behind the bumber then cut a perfect square hole in the cladding below the bumper for the reciever. I did the lights myself. I took the left (doesn't really matter which one) tail light thing out and apart and soldiered in wires and a connector. Bought a 3 to 2 light converter and put on the mating connector then dangle the wires out the trunk to connect the trailer, it doesn't seem to bother the trunk seal. I have a 4 x 8 foot utility trailer and so far everything has acted predictably.