Hambone, the only time you should have to use that slot would be after a brake job to get the shoes close to the drums. Adjust the shoes out until you get a noticeable drag, then pull the adjusting pawl away from the star wheel with a hook tool and back it off 15-20 clicks. Once that's done, the self-adjusters will fine tune themselves after a couple of dozen stops in reverse.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!