So i got to changing my glow plugs yesterday and i get to #4 and the head was already messed up..... i know the PO didn't wrench on this thing himself so some mechanic left me this little jewel. I tried to get on it with a wrench that hit on the flats and nothing. Luckily i have a set of these extractors that i used to use when i was in business and they saved the day.
Link:
http://amzn.com/B0000CCXVZ