I can see what John is saying about not digging myself into a hole of having two non-runners sitting in my driveway. Because of that and because the cooling system doesn't look so bad (upon further inspection), I will leave it be except for potentially multiple flushes.
I got a lot done in about two hours today! I pulled the alt, unbolted and moved over the PS pump, pulled and emptied the coolant reservoir, and organized all of the parts that I have pulled so far so that I'll remember how everything goes back during reinstallation. Basically, all I have to do is pull the coolant line running across the manifold, unbolt the valve covers, and then I'm ready to pull the IM!
My trunk is growing ever fuller of parts:
This is the one confusing thing: that is all of the coolant I have managed to get out so far. The system supposedly holds 11-odd quarts.
I'm clearly missing several quarts of coolant. Where could it be? I've concluded that there is no drain plug on the rear of the block, so that means that I've basically done everything right so far (as far as I can tell). I forgot to check the oil, but last time I had a look, it seemed pretty good-looking.
My sister was saying that I should fill the system with water to see what it takes to fill it. It sounds like a good idea to me, but at this point I've disassembled enough of the car that I definitely should just complete the IM gasket job before trying to hunt down my missing coolant in ways that would require running the car.
My one concern, and maybe it is a little silly, is that there somehow is coolant hiding inside of the manifold that is waiting to spill all over the engine internals the second I pull of the lower manifold. Does this even sound like a remote possibility?