I've always used a big pair of Channel lock pliers on those threaded dust caps, or a pipe wrench on the stubborn ones. Adjusting the brake shoes to lock the drum helps if it's necessary to apply a bit of persuasion.
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!