I have the stock 4 pole harness. In October I'm going to be renting a camper for a few days, and it has a 7 pole harness. The owner of the camper tells me that I'll need to have a conversion physically installed, that there isn't a simple adapter I can just plug in between my harness and the campers. Is this accurate? If so, can anyone recommend a decent conversion that I can purchase? Ideally something that doesn't involve drilling into my bumper; if possible I'd like to mount it to the frame somewhere behind my bumper so it's out of sight. The owner of the camper said its wiring is plenty long enough to reach behind the bumper.