Editing system keyboard layout I wonder how to edit the following two files, so that I can change the system keyboard layout. It seems they are binary resource files, but I'm not sure.

/System/Library/Keyboard\ Layouts/AppleKeyboardLayouts.bundle/Contents/Resources/AppleKeyboardLayouts-B.dat

/System/Library/Keyboard\ Layouts/AppleKeyboardLayouts.bundle/Contents/Resources/AppleKeyboardLayouts-L.dat


I could use Ukelele to create a custom layout, but I would like to know how Ukelele reads the current layouts, and more over whether it is posible to edit the system layout directly.
As far as I know, nobody has found a way to edit the system layouts directly. Making a custom layout via Ukelele is the way to go.