No problem, did you get the head face surface skimmed(made totally flat) by machining before you put the head on the engine,
How your gasket has blown out may be down to the head or the cylinder block not being aboslutely flat, as the gasket you used are a very good gasket, and being fibrous and not steel cope much better if the surface of the head and cylinder block are not absolutely perfect, so odd at that boost it should have gone.
I suspect the head or block is warped.
Also what did you use to clamp the head to the block, did you use the ARP stud and nut kit or the standard ford headbolts ?, and if ARP what torque(lbft or NM) did you do them up to ?
tabetha