[Guy]

If you really want to shut the valves on the road there is a simple way to minimize the potential of them leaking. Before closing the valve, loosen the nut that is below the handle. That nuts tightens the packing around the valve stem. Tighten the valve, the retighten the nut around the stem

The reason I didn't is that the "plumbing" of the hoses makes no sense. I am totally confused by the two lines that enter the system to the top radiator tank. It appears one of them joins the system just past the point of the engine shut off valve. Since coolant loss   has stabilized for the moment, I will remain hyper sensitive to engine temps and coolant level. I am think that any havoc I bring to this coach in Rodeo New Mexico, Pop 101 could lead to a really expensive day.