on Apr 30, 2017 12:32:07 GMT
Welcome to the Forum danieljmf!
I have not seen a schematic for the construction of the lens other than the one showing the elements/groups so I'm sorry that I can't be much help but maybe someone here can. I've misplaced my copy of the lens but if I find it, I'll get back to you with any possible suggestions; can you identify which element groups have the fungus infestation as that may help determine whether you should go in from the front or the back?
You say that you've taken apart lenses of this age so I assume you have a set of JIS screwdrivers - whatever else you do please don't use Philips cross-head screwdrivers or you'll run the risk of stripping the heads. Yashica had a practice of adding glue to some of their screws so be very careful when trying to move them, especially those on the mounts.
Hopefully someone here can help you...