What does 'not necessary' mean in this context do you think? I don't find the information consistent.
From my experience, "not necessary" means "not needed" which, in the context of that modification, would also mean that he believes the original K100 centerstand would function with the new setup.
The information he provides seems clear to me. He wrote that he was breaking new ground by modifying his K100 this way and you are breaking new ground for yourself by modifying a K75 in this way, if you're successful.