NASA Saturn V Stage 1 to 2 additional coupling ring

If you are thinking of printing the Saturn V from the NASA web site (from here https://nasa3d.arc.nasa.gov/detail/SATURNV) then I found it has an error (IMHO) in the model for Stage 2 at the base. The coupling ring model doesn't mate at all to the bottom of Stage 2. When you assemble the parts you get a 5mm gap (pic - I turned the coupler upside down just to illustrate the point, I'd already glued it on before doing this summary!).

I printed this extra ring which you glue onto the base of St