Mark- Dick's advise is absolutely correct. I've had two experiences simnialr to your is the past decade, one on a friend's 49 Plymouth- took us three weekends of heating , Rust buster, and hub pulling till one moment- surprise- the drum popped! Persistence & mystery.the other was with Clark Thomas on a 62 LeBaron we were preparing for transfer of caretaker. We discovered that the drum would 'stick' in one palce on rotation, and we worked after many days on the spot it was 'free'- after reducing the shoe pressure against the drum to bare minimum. What we found when the drum finally popped- was the linings had detached from the shoes. Maybe your linings are riveted and not bonded- but just wanted to mention that if the rivets popped- the 'loose brake lining' could be contributing to your problem. I had that happen on an old Chevy when I was a college kid-the linings were ruined by brake fluid- which 'cracked the lining'- and the linings came 'off their rivets'. .Calif sounds great, but being on the east coast--- Best wishes for a happy holiday- and success!Sherman--
Sherman D. Taffel
Taffel Engineering/Taffel Vintage Motors
6001 Jamina Downs
Columbia, Maryland 21045
410-302-3930