I did this on a junked rotring core pen, it can write but its very scratchy on paper, the tip has been flattened slightly and the feed shows some damage as well.

I don't know if what I did to disassmble it should be done on a working one.

Removing the feed from the section:

I ended up using a pair of pliers by gripping between the nib and the feed right next to where it meets up with the section and then pulling with enough force to unlock it from its snapped position. It was easy to re-insert it back into place and locked back in.

With a proper set of pliers that can grip it in the right position I don't think there could be any damage done to the nib. But I wasn't using proper pliers for this trail run.

After removal of the feed from the section, the nib is still firmly in place on the feed, although it appears that the nib was slid onto the feed, I don't have the tools neccessary to slide it back on or off. Rather it looks more like the nib was "clipped" onto the feed. I used a narrow flathead screwdriver to wedge just one side of the clipped metal off of the feed, from there it was easy to remove the nib. Reattaching the nib was easy just push it back in the opposite way it was removed, and used a pair of pliers to snap it back in place.

Am I using the wrong tools for this job?