O.K.---it isn't quite as I had first said. The big hex nut at the bottom is a locknut, which has an adjusting screw that turns in or out to bring the shoe closer to the drum. You loosen off the hex nut, then turn the adjusting screw untill you can feel the right amount of "drag" on the wheel as you rotate it by hand, then you retighten the hexnut.---then you adjust the 11/16" hex nut/eliptical cam which is located about 2/3 of the way up the backing plate, again untill you feel the right amount of "drag" as you try to rotate the wheel. I readjusted both front wheels (4 adjustments per wheel) this morning, and all seems to be fine, I gained about 1 1/2" of pedal after the front brakes were adjusted. The rear drums are on a 1985 S10 rearend, with the self adjusting shoes, so I did the "back up in the driveway and put the brakes on" thing to adjust the rear shoes.