I'm changing the upper intake manifold gasket and valve cove gaskets. I have to remove the coolant line/tube from the intake manifold that feeds the heater core (to get it out of the way). what's the easiest way to drain some coolant so it doesn't mess when I remove said tube?

 

Does your truck have SAI? If so, you can pull the temp sensor in the radiator to drain some out, Otherwise, you have to pull the lower radiator hose.