How do I delete third party plugins from GarageBand?

I've deleted every file I can find to remove some plugins I don't want, but when I open GarageBand I still see them listed as options to use. They don't work but the plugin names are still there. It's ridiculous how difficult it is to remove these things. I've contacted the creator of one I want removed but have heard nothing from back them.

It should not be so difficult to add or remove plugins Or Loops and sounds.

GarageBand 10.04.11 version