1) What intake are You running?
2) Are You using end-rail gaskets, or just RTV, plastic retaining dowels for such in or out?
3) The gasket is not just pulled away, it has shifted towards cyl. #4 both times?
4) I'd get carbonless paper from Goodson & bolt the intake down w/the heads bolted on w/the gaskets, see what contact pattern shows.
