Re: weird trailer wiring connectors
Those two identical 4-connector jacks (actually one should be bigger than the other) is for hooking up to trailers, and I think for ones with electric brakes or back-up lights. Because three of the wires on the larger 4 point connector can be spliced into for a universal trailer wiring kit, and the only wire left will turn on driving lamps if you put some on for better backing up light. After I spliced into the wires I had my trailer going and had some good back-up lights.
I know because I got the connector kit that said it was for F-150's/Bronco's from Auto Zone, but it did not work. So, I used a probe to find that on the 4-connector plugs you can find the Brake/Turning and running lights out of the wires.
I do not remeber the wire colors, but a probe will tell you. Also, I do believe that you can find the male plug that will fit in that 4 point connector and just splce into the ends of those wires.
Hope I was able to help