Thanks for the ideas. I understand the need to drain the block, radiator, and heater core. And I also understand the need to flush out the entire cooling system once the coolant is drained. But what do you guys do with the "flush water"? I can't very well just let it drain into the street, because our storm drainage goes directly into a local stream. That's the whole issue that got me thinking about the Liquivac. I thought that I could do repeated empty-fill cycles and dispose of the waste water properly, keeping it contained. This was assuming that I could gain access to the basal recesses of the block. I know that the radiator should be no problemo.
Still, it is interesting to see how other folks do their coolant changes.