Try a Snap-On socket, they will bite in when other will not. Or try using a metric deep socket, it may fit a little tighter and may need to be tapped on. I would spray some WD-40 or simular around base for plug. Just in case its siezed.
[FONT=Trebuchet MS]01' Jeep TJ (Jeep #5)
3.5 RE Custom SuperFlex, Raingler, Kilby, Currie, Banks, Borla, American Racing, Custom mods, Always more in the works.