I tried doing a search here but couldn't find the answer I'm looking for.

I need to install a wiring harness into the tail lights of my Cherokee for the lights on my boat trailer, which has a "flat 4" connector. I saw two by the company "Hoppy"(?)- both which need to be spliced into the wires going into the tail lights, which I can do. There was one which was for "Independent turn signal vehicles"- it had a power-pack looking thing-y where the flat 4 connector is. Do our Cherokees have independent turn signals? Because the rear signals are the yellow ones, not shared with the brake light like alot of vehicles, I thought maybe thats what I need..

Do I? or do I get a simple one with no power-pack thing-y?

Help!!