I accept the knowledge possessed by these guys. They are absolutely tip-top. I do have one question and it is for my curiosity.

Where on the head or gasket does the oil get into the coolant? Between the cam oil feed ports and the cooling passages? I honestly want to know and I'm not trying to cast doubts.

I ask because I dont know of any place above the crank journals where oil pressure exceeds the coolant pressure. The cam feed ports are the only place I can imagine the difference but I am not savvy enough to know what the actual pressure at the ports is.