Bought a Prera recently so that I could switch its nib with a BB italic from a Pilot Plumix that wasn’t seeing much use. This turned out to be simpler than I’d expected.
Grasp the nib and feed between thumb and forefinger and pull straight out. Don’t twist. The feed and nib will emerge together.
The Plumix first:
(Note the different ends on the feeds from the Plumix and the Prera. The Plumix is a bit different from other Pilot pens as it takes international cartridges instead of Pilot’s proprietary ones.)
Then the Prera:
The nib is shaped so that it’ll fit in only 1 position on the feed. I switched the nibs, then pushed nib and feed back into the section.
Voila! With the BB nib the Prera is even cuter 🙂