etrailer.com has wiring solutions for your vehicle. Generally you are going to need to use diodes to prevent feedback into the car's circuits. These kits will have complete instructions on how to do it.
You will need to determine if you have a three wire or two wire system. The three wire system uses a separate turn signal light while the two wire system uses same bulb (with two filaments) to provide tail lights and turn/stop lights. If your motorhome uses the two wire system and your towed uses the three wire system, you will need an adapter as well.
Roger & Mary
2017 Winnebago Navion 24V
2014 Tiffin Phaeton 36GH (Sold)