champlainl

got an '06 f250, 236,000 miles, changed plugs and cp's,champion plugs, changed them all to motorcraft 515, my issue is #2 cylinder plug broke, hex nut broke off threaded section, porcelain part came out in one piece, now threaded section and bottom sleeve still in head. Easy out with 2 ft breaker bar and nothing moves, heat and breaker bar and still nothing. Very frustrated, and yes I used penetrating oil. What next? Lisle too won't work either because threaded section still in head,Please help. Thanks