@Chris
The Zebra nib is going to be tight too. To make it less tight perhaps you might have to use sandpaper (or something else) to make the feed smaller so that the Zebra nib can fit in a bit more easily. Then there's the issue with ink flow because this feed is not designed to heavy ink flow but it should not be a problem if you're just writing slowly.
@Chris
The Zebra nib is going to be tight too. To make it less tight perhaps you might have to use sandpaper (or something else) to make the feed smaller so that the Zebra nib can fit in a bit more easily. Then there's the issue with ink flow because this feed is not designed to heavy ink flow but it should not be a problem if you're just writing slowly.