I did release each bolt individually before retorquing it and then move to the next from the center outwards (forgot to mention). I did not remove the radiator cap when I retorqued the bolts for the first time 6 months ago, I did not know and possibly that created the leak.
Tyler, I will try to make some fitting to pressure test, you gave me some hope. I witnessed a few blown gaskets and there is always a lot more, smoke, noise, rough running, overheating and I have none of these. The engine runs perfect, not a puff of smoke at start or later.