Hi Dave,
I have removed doors from 6 or 7 600s and nearly every pin was a major pain to remove. I have tried WD40 along with a large drfit and still had trouble. About the only way I have found to remove them without damaging the pins or hinges is to use heat to expand the hinge metal. Unfortunately, you will damage the paint this way though. The pins hang down a little, so you can try tapping them first, but be careful not to deform the pins. When doing this, you should also put a piece of heavy metal (as an inertia block) on the top of the hinges.
I had one 600 in a body shop once for restoration and customizing, and even they had trouble getting the pins out. One was damaged, and they had to make up a new one (from a bolt). If your hinges and/or pins are worn, you may need to install new oversize ones.
Good luck!
Gil
