[russcc]

Here is another method that was used to get an old set of aluminum heads off. They were really stuck. An old time Model A guy suggested cleaning out around the stud hole perimeter in the heads as best you can, and use Kroil around around all the studs. Let it set for a day or two, and add more if needed. Off the old head came. If it worked on aluminum heads it ought to work on the cast iron heads as well.