But on reassembly, make sure the brake is setup properly. Reassemble it onto the bike with the wheel, etal, all attached, but with the axle and brake nuts loose. Make sure the chain is adjusted where you want it. Tighten the brake backing plate nut slightly (The big one behind the axle nut) and tighten the brake adjuster nut down to lock the brake and center the shoes. Then tighten the rest of the nuts, the big one first, the axle nut, then the pivot pin nut. Adjust the brake adjuster nut to the point you want the free play. I usually use about an 1/8" of pedal play.
This will insure that both brake linings are against the drum, when applied, for maximum braking. They won't be fantastic, but you should be able to lock up the rear wheel when wanted.
Bare