A friend cut and drilled a piece of flat-bar,using the old head gasket as a template, and with a piece of wood in the bore,I used a breaker bar with an extension and got the nut to come off. It was on there tight.
Pic of the set-up
pic of the head on
I had a tough time too, I put some antiseeze on it when it got reinstalled and some grease around the outside ...If I ever have to take it off again I hope the rust cant get in there anymore.