Followed your thread and Ford really doesn't make it easy.
You're certainly blazing a trail and unfortunately that means you're on the bleeding edge before the leading one but i think you're getting close.
If the harness works "as advertised" you "should be" good to go.
Would this be the answer to your problem?
http://www.infotainment.com/collections/installation-components/products/ford-aftermarket-amplifier-audio-harness