In ups.com,
Ray wrote:

...The G2 refill is shorter than the
Montblanc rollerball refill. Even so, it won't fit, because it isn't
threaded like the Montblanc rollerball refill. It simply wont insert
far enough into the pen. Even if you could insert it all the way, it
wouldn't be functional (at least without a spacer of some kind). It
would move up and down due its shortness and the lack of threading.

So it looks like you'd have to do something like swap the endcaps of the
refills and machine (turn down or tap) the lower step of the G2 refill --
which might not be possible, unless the plastic is really thick there.

Well, something might still turn up, so I hope other people read this
thread. I have a 1950s Waterman "Sapphire" ballpoint, and I thought
*nothing* current would fit it (it has an unusual form). I heavily modified
a Cross refill to fit... then found out a Cartier "Must" refill works.

Brian
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