Ok, I guess, for the mount on the pack, but for the mount on the belt, what is used in the movie is a small clip. They don't use the same mounting mechanism as for the pack. Take a look in the first movie, when Ray walks in the Sedgewick Hotel, smoking a cigarette, or Egon (just as good scene). Look at the way the gun is clipped on the belt, you'll understand.
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Canadians Ghostbusters Kick A$$ - Ghost a$$, that is…
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