A little heat usually melts the loctite did you heat the stud or the cases and how hot? If you heated the stud, the steel expanded and made it a tighter fit. Heat the area around the stud with a propane torch and only lightly. Take two nuts and lock them together to prevent damaging the stud. Using pliers ruined the OE ones so I would get some Kibblewhite or Ramjet studs and set them according to the service manual.
I have never had a problem removing studs this way.
You can reuse stock studs if undamaged and not over torqued. Still, replace them all with stronger stuff and then you don't have to worry about it.
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