Vintage Mb 144 Repair Question

[Pathian]

Hi all. I had an unfortunate mishap with my Montblanc 144 where it snapped near the thread end of the section. The feed didn't appear damaged, so I got a donor section to replace it with, but the nib and feed seem pretty firmly set in the old section. I don't know the specific date of manufacture, but it's a 14k monotone nib with the style of feed pictured below (not my pen, image from Peyton Street Pens). Are there any tips/tutorials for removing the old nib and feed? Or is this a job best left to a professional (if so, I'm open to recommendations)? Thanks much!