I made a mistake defining a custom scale and now I can’t delete it. It stays there and reminds me of my mistake and messes up with my choice when I need to pick a proper one.

How can I delete it without reinstalling the whole app of purging some settings in some file, buried deep in the extensive bowels Illustrator has?

Then — I don’t need some of the default scales it has. How can I hide these, to go to my defined scales faster?