You do not need to do any wiring if you are towing with a tow dolly or a car trailer. Both the tow dolly and car trailer have lights and there is no requirement that the car lights be used.
If you want lights on the back of the car (even though they are not required, buy a set of magnetic tow lights such as these from Harbor Freight
http://www.harborfreight.com/12-volt...kit-67455.html