While there are various tools for this, my experience is that broken bolts theaded into an exhaust header or manifold are probably not going to give way to any extractor, particularly in the case of small fasteners.

Probably easier to drill and tap one size larger, if possible.

The Alden Drill-outs would probably offer up your best chance, but do not expect too much in this case.

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1986 300E 5-Speed 240k mi.