Kevin, If that breech plug has never been out it can be a real bear!! That's why I never suggested it. If you have a safe place, buy yourself a couple gallons of diesel fuel or Karosen and let it soak in that for about a week.
That will help a little in most cases. Make sure you have a good vice mounted to a super sturdy bench or table and a the last time I took one out i had to use a pipe wrench with no teeth. They are used for drain plugs. I'm talking about a 2' long handle on that wrench.You may need to heat it real right at the joint .