Some more specific answers to Sourner's questions are:
The WAGR railcars corresponding to the Redhens were the ADGs and ADXs.
The ADHs, when built, corresponded to the Bluebirds, and were only later converted to become similar to the ADGs.
The ADKs had no real SA equivalent.
The ADLs corresponded to the Jumbos.
Steam to diesel happened in 1969, and diesel to electric in 1991-92