HYCON Lens Element Spacing?

Anyone possibly know the exact separation required between the two
elements of the Goerz f/4.5, 75 mm Hycon lens (copy of Biogon)?

Distance between the facing glass surfaces-- and/or the surfaces of
the two facing permanent barrel flanges-- would be greatly
appreciated.

I have deduced the distance from the patent filed for this lens
design but it is based on a focal length of 100 mm, not the 75mm
lens produced circa 1955.

Thanks for information or possible other sources for this
information.
Bernard