Liked the original, but wanted a 6 ring version for 6 number combination or a MMDDYY date format.
I altered the inner shaft and the lid to fit 6 rings instead of 5. Also, I had trouble importing the bottom of the lid, so I modified it and made it flat. I don't think you'll notice the difference, and more importantly, my printer liked it better.
So just print these shapes in place of the inner tube and lid from the original set!