Holy shite. I'm running the BD right now and I think it's working. When I first started pouring it in the smoke was billowing out from under the manifold as it had been. After a couple minutes it stopped. No dripping under the truck. Temp is stable. The engine even seems to be running smoother (perhaps that part is my imagination).

I'm keeping my fingers crossed!

Does anyone know off top of your head which sensor on the thermostat housing goes to the dash? There is a 2 prong one and a one prong one. It occurred to me that maybe it got cruded up when the radiator started getting rusty inside.