Try bolting the wheel on without installing the screws and see if the drum locks up that way. If it does, you've got a problem with the drum or the assembly of the brake. If the wheel spins OK with the screws gone, the screws are probably too long and they're binding on something behind them. Also check to see if the drum is dragging on the backing plate with the screws tightened. You might have bent the backing plate while trying to remove the stuck drum.
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!