Keyboard Shortcut to check and uncheck "Show all formatting marks"



I can't find this command in the 'customize keyboard shortcuts' dialog box.
Maybe it's because the check box is in an unusual place:

Office Menu > Word Options Button > Display > Show All Formatting Marks

Any suggestions as to how I can attach a keyboard shortcut to check AND
uncheck this one?

Thanks,

-Mike Behrens-
.