I removed the dust caps and threaded in my crank puller. When I tightened it down, it simply push out the threads destroying them. Now, I have no way to remove the crank with a puller. Did I use the wrong type of crank puller. Is there a special version for these Shimano Octalink cranks? Any ideas about how to get the cranks off? Are they ruined and will I have to replace them with new cranks?