Hi, John. I'm finally getting the alternator on the 1800 and was noticing between the head and the valve cover there seems to be a piece about 1" thick, front looks like it's maybe the bottom of the thermostat housing. What is this? I've never seen anything like it, except where someone wanted to "stroke" an engine and needed more clearance on the top end. 
 The reasn I ask is one of the ears on the casting for the thermostat housing is broken off on this 1" thick piece. It's not leaking, just wondering. 
 Hope you folks are done harvesting. It's rained around here for the last 2 weeks. Everyone around here is mostly done, thank goodness, as the fields are saturated now.