Exhaust manifold stuck to the head

[dzwestwindsor]

Hi guys,

I'm trying to remove the exhaust manifold on a 1971 chevy 350. Since 2 of the bolts connecting the manifold to the cylinder head are rounded, I used a Dremel to grind the bolt heads. Now, I have 4 bolts removed and 2 bolt heads grinded down. That's all the bolts holding the manifold to the head (6), correct?

I'm asking because the manifold will not budge at all. I've whacked it many many times with a mallet and sprayed PBblaster, but to no avail. It would even budge...

Does the exhaust manifold fit into the cylinder head? Like does it fit into the head like a socket? If all the bolts are actually removed, would it stay on by itself or should it just fall off?

Also, is it okay to take a bar and pry the thing off, pressing on the valve cover to get leverage? Or will that damage the valve cover?

I'm having trouble figuring out what's still holding it on. Just flat out rust? Or am I forgetting to remove a bolt from somewhere? Any advice?

Thanks,
David