Global guidelines are nested in font objects, and local guidelines are in glyph objects.
Aha! That makes so much sense, yet I never thought about it. Thanks @Ryan :)
I quickly wrote a script that adds local guidelines with specific coordinates for a list of glyphs.
That way I can define the overshoots for /O and /o (that's usually two of the characters I draw in the ideation stage already) and put those values in the code that then adds the guidelines to the list of glyphs I defined and where I need them.
It’s not a very "programming" way of doing things, but it gets the job done and it’s pretty straight forward without having to many places I can make mistakes :)
I was even thinking about making it a small tool or something inside the inspector where one can store the values for UC & lc and on click remove or add local guidelines.
Who knows, maybe I can make Tals tool work for me, then I don't need to do anything by myself :)