Rear Rotor Replacment problem.

Hello. I've been a C3 Fan for years, since I was 14. However I am now the proud owner of a 76 Stingray. Anyway, I am replacing all rotors an Calipers, but I am having a real hard time on the right rear getting it over the emergency brake. The Emergency "drum" brake shifts up from one side or the other when I try to fit the rotor back on. Any help on how to get past this little problem would be a great help.
Thanks
TravBro

Check and make sure the brake shoes are adjusted in, and check to be sure the shoes are both sitting on the anchoring pin. If not, the brake cable is sticking or adjusted too tight. This will cause your problem.