It appears that one of the pi heads I bought blew a plug at some time. Of course, I didnt bother checking this before possibly wasting a gasket and tty head bolts. Someone must have had this problem before. I've done several of these and this is the first one I've come across. Needless to say, this will be on my list of thing's to check from now on when doing a pi swap. They have different spark plug repair kits but either the tap is too small or you cant get the required size socket in the hole for the tap that will work. I'm defeated today. Does anyone have any suggestions? They have one kit specifically for 4.6 and 5.4 for about 150. It would be cheaper just to pull the head and buy new bolts and gaskets. Im trying to do this without pulling it. Thanks