Folks... A quick search resulted in multiple posts with ideas.
Many people do this, and apparantly it was an option from the factory.
IMO, hanging bikes off the back is a very bad idea (i've seen too many bikes still attached to the racks laying on the side of the road.
There is a company that builds a rack that goes above the propane tanks on the front. This makes more sense to me as you can see if there's a problem with the bikes, and the back of a trailer bounces a ton. Hitch not so much.
I'm looking at getting a roof rack for my TV, because I need to carry two bikes and a two kid chariot.