one other thing, the exhaust flange bolt from the manifold/header is rusted to the point I broke my craftsman universal in half at the socket connection!!

I have access to the flange with the dremel and wanted to know if I cut the bolt off would I be able to have a new bolt installed in the manifold so I can put the flange/exhaust back together? Or is this a bolt that's molded into the mainfold??