I went with the light kit by DemCo, which I ordered when I purchased the tow bar. If I'm not mistaken, to wire the automobile lights with the present lighting system you will need a diode kit at a minimum.
Try RVUpgrade Store
or search on "RV wiring kit" on Google.
I'm not sure if this is what you are asking for, but here is a variety of wiring diagrams Wiring
p.s., my personal preference is to add a set of lights to the existing glass (plastic) housing already on the vehicle. You just drill a hole for a new light socket and do not have to rely on the tow vehicle battery system since it is wired to the coach lighting system with a quick disconnect.