Dear Bill
I followed your link in a search to constantly improve my understanding of the SM2K systems , and liked the safety feature of being able to isolate any system not in use during navigation. I must admit that I don’t know if it is doable on mine (2005) but I can see on your updated diagram after the addition of the 2 breakers that you now have 2 breakers in line . Was it necessary to leave the first one in place ? 
Thank you for your un valuable postings , I now know the difference between  SPST, SPDT ,DPST & DPDT 
As they say …a step at a time ! 🤓
Kind regards
--
Nicolas Klene
DarNico
SM2K # 471
In Marseille