Painting drums isn't a bad idea- - - - -it's a TERRIBLE one. Drums have to dissipate the heat from the friction the shoes develop, and paint is an insulator. If you want to blacken the drums, use a little "stove polish" on them. It's basically carbon black suspended in beeswax. Those gear-shaped pieces are supposed to mesh with the adjuster wheels on the ends of the wheel cylinder and allow you to adjust each brake shoe individually. Do whatever is necessary to restore the adjusters to their proper function. The bolt-type adjusters are unique to the 1-ton brakes, I believe. 1/2 ton Huck brakes have slots for an adjusting tool.
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!