Got a pic of that frayed spot? Curious how bad it looked.

Check the gage at the Ponca low water bridge before you commit, and if it's up just take the ridge route from the start instead of wasting miles. Saved me the same headache on that stretch last spring.

Learned that same double wrench trick from an old timer and it saved my butt on a caliper bolt last winter. He called it the poor man's breaker bar and I laughed until I actually tried it. Key thing he showed me was to keep both wrenches flat against each other so the jaws lock up solid instead of slipping off the hex. I've also used a box end on the bleeder with a long combo wrench hooked into it for even more reach when there's no room to swing a big bar. Your point about it being a torque problem and not a rust problem is spot on, I've wasted way too many hours soaking stuff that just needed a longer arm. Going to try your heat plus soak routine first next time though, sounds like a good combo before reaching for the wrenches.