06 5.4l 3v spark plug thread stuck in head. Juts the thread the bottom cone peice removed. Tried square and spiral style extractors the square I get a bite and I and using 6inch extension and a long reach ratchet no budge

 

Same issue is addressed by the following posting.
2004 - 2008 Ford F150 General discussion on the 2004 - 2008 Ford F150 truck.

2004 New body style 3v spark plugs

Your solution path may differ but same sort of problem

 

They make a tool for this.