Where is it leaking? Between cyl. 3 and 4 on the front?
When the engine was remanufactured do you know if the head and deck surfaces were re-faced?Small warpages in these two surfaces often lead to localized leaks, particularly with the metal head gasket used on AAZs. If this is the case there's no real cure except to have the surfaces re-worked.
I don't know of a fiber gasket for the AAZ.
copper and aluminum together do bad things.