351w deck tolerances

[Justin]

Posted this in my build thread, but figured I'd ask it here. Was told by the machine shop the head deck on my 351w block didn't need to be milled, so I didn't. Got it built, and discovered a head gasket leak on the #6 cylinder. With a straight edge going across the top of the cylinders I can slide a .002 feeler under it, but not when the straight edge is held diagonally. A .003 doesn't fit at all. Is this too far out of spec to get good head gasket sealing?

Also, while it's apart, I'm considering switching from head bolts to studs, but it's $130 I don't want to spend if there's no real difference. Thoughts?