tough section to remove

[Sagebrush64]

So I've had this beautiful green celluloid Wahl/Gregg lever filler for some time now and have been stymied on every attempt to try and remove the section.

I've done this simple procedure dozens of times and have always triumphed, but his pen just won't let go of the section. I'm starting to wonder if it was super glued to the barrel (it has an incorrect skyline nib/feed from a previous repair).

I've done the soak, heat, soak, heat thing probably a dozen times with zero results. Can anyone out there give me some alternative tactic to end this silly game?