okay...update.
ripped (well, removed) out the carpet in the rear trunk. And there was a little coolant on the metal floor pan. However, it was no "lake". I would say all in all it would have equaled a few table spoons. mostly it was a thin coat of slime. I wiped everything up and refilled the tank (which was down @ 1/2 gallon). I then jacked up the car to see if maybe it was leaking down by the passanger rear wheel. Dry as a bone, from what i can tell.
so now i am really confused. where is the coolant? The car runs as smooth as snot, so i am praying its not a head gasket issue.
but even though it was not much, that coolant in the trunk had to have escaped from somewhere in the reservior, right? maybe since i live in an extremely dry climate, some may have evaporated?
also, i did notice that i have the old (pn. 00) cap. I will be ordering the new one. maybe i will get lucky.
any thoughts?