Replace General Appearance Icon

So I have a genuine Mac. I am looking to replace the old General Appearance icon, but I can't seem to find it at all. I know that a lot of the system icons are located in /System/Library/CoreServices/CoreTypes.bundle/Contents/Resources/

But I can't seem to find the General Appearance icon I have attached to this thread. I know that the Appearance files are located in

/System/Library/PreferencePanes/Appearance.prefPane/Contents/Resources/

But there aren't any image icons or any images in that location. Is there an exact location to replace the icon attached to this thread?

Does anybody know how to do this?