Both of these websites are actively cataloguing the vast number of CRTs in existence, complete with specifications, service manuals, and photos. They also provide extremely helpful guides to help walk through some of the more complicated repair procedures.
Good question - CRT Database has some articles covering it. There’s also this large shmups.org thread with a lot of detailed technical discussion, but would probably take a while to parse.
Retro Tech on YouTube also has several videos covering RGB mods too, if I recall correctly.
This looks promising:
https://consolemods.org/wiki/CRT:RGB_Video_Modifications
It appears to be a sub-section of the CRT Wiki in your post.