i will compression test today - but there are no erratic idle or stalling issues. It holds a steady 900-1k RPM idle, it just shakes like a blender while doing it. I've never seen any smoke from the car; headgasket should be good.

Hopefully I don't have to pull the head, but thankfully I have a second car to drive around in the event it needs to be pulled this winter. How big of an undertaking is it? Assuming I keep everything marked at TDC I won't need to retime, yes? I loved being able to easily remove the cams and keep timing when I did the valve adjustment... my S54's timing is much, much more complicated...