Trailer harness kit includes mysterious plug

I have a trailer harness kit that came with my '98 Windstar. There is the cable that connects to the plug under the rear bumper area. I understand its purpose. But there is also included another plug module with a set of wires coming out about 6 inches long with no connectors. What is this for? Does this connect to the plug under the driver side console and have to be spliced into a set of wiring?

I know on the F-150 they include the harness to incorporate electric brakes into the tow package, but you have to connect it yourself. I bet that's what the harness is. Check the owners manual, I beleive I've seen the install instructions somewhere and I beleive that's where.

Denis