Broken and unbreakable bolts HELP

Oldmanmopar Thank you your concerns are exactly the same as mine. I know that cast iron tends to be soft. I think one of them I may be able to get out with a vise grip and I going to try once I get the manifold out. The other one I think I am going to bring to a machine shop. I really don't want to screw up because I can't afford a replacement.