Last time I changed my drums, I pried it off and the old drum and installed it on the new drum with a block and mallet. Not sure if that's the propper way to do that though. Maybe someone else can chime in here.
Parking Lot Hero
2008 WRX daily driver
2003 ZX3 23D Autox Car 42 FSP
"Hella Functional - Raced, Not Hard Parked"