Philminotti Phil do you have both gaskets facing forward even though one is upside down??? Tork to spec, if it still leaks you are pulling the head. Are you using #1020 felpro gaskets?? I use them and High-tac the crap out of them and have not had a leak in 8 years of the 452 and 3 years on the 482. Straight edge the block and heads too start.
Rick L. PS Phil that head should have been checked before the heads where box for shipping, hence the word machining. Since it's the right side of the motor, check the head gasket for being on right. There is a thread on this either here or on the FE forum to see if the gaskets are on right with the gasket sticking out a certain way on both sides. Maybe someone else here has that thread number. try this first.