I use 120 film with adapters in a Kodak Six-16, which of course uses 616 film. 616 film is identical to 116 film, save and except the 616 spools have a thinner centre bit, slightly smaller flanges, and a different hole at each end of the spool.
For my camera, the red window is in the right place to use the 12 exposure numbers on 120 film. So as 4.5 inches is exactly twice 2.25 inches, I can simply deal with this by stopping at 1, 3, 5, 7, 9 and 11.
I'd suggest sacrificing a roll, or retrieving some backing paper. You can then experiment with comparing where the film advances to with how things appear in the window.
If you get stuck, I have four 116 spools that I ended up with when I was looking for 616.