UPDATE FROM THIS WEEKEND.....
We headed out Thursday morning for our trip. I never even made it out of the driveway before I started getting the "OL" signal, and then it went to a constant "SH" signal.
This was good because it would give me an opportunity to trace it down while the brakes were not functioning correctly.
I crawled under the trailer and pushed, pulled, and yanked on every set of brake wires I could find. Nothing stopped the "SH" condition.
I followed my plan and cut away the rear axle feed line. As soon as it was cut, the "SH" went away, and the rest of our trip out and back was perfect.
Good brakes the whole time. So now I know it's on the rear axle, and since I have replaced all that wiring, it must be inside one of the hubs. Time to take them off and do some inspection I guess.
Thanks,
Jerry