OK folks. Problem solved. I wanted to post it here so that if other people have the same problem in the future, I hope this can help.
The
"Brake Control Plug" is that
"4 pin grey connector" on the right/bottom side of this picture (as I have previously suspected).
This is the
"Ford Supplied pig-tail connector" that came in the bag, with my manuals.
I purchased this "Tekonsha Pig-tail connector", that I spliced into the Ford Pig-tail connector. Also shown in the picture is how I connected the wires, using the decripstion on "Tekonsha's Color Code and Description"..... AND "Ford Pig Tail's Color Code and Description". (I hand wrote the corresponding codes to the right side of the desscription in Tekonsha's docuement).
I also purchased this Curt 7-pin Tester from Amazon. Everything checked out and function after I plugged all connectors and after I plug the Teckonsha Brake Controller.
WE ARE NOW READY TO TOW OUR DOLLY/CAR.
Thank you all for your help. I am hoping this help other folks here in the forum.