Just curious, where is the spark plug "broke off" at to have to remove the head?
BTW, I would not go with Cometic, if you feel the need to run a MLS style gasket, go for the Fel-Pro version of them. I just ripped my pair off in disgust for seeping coolant out from between the layers (definitely not the first to experience this) and slapped some 1011-2's on there. I am sure the kit came with a fel-pro version head gasket equivalent to the OEM version picked up at the local auto store.