BSB
I don't know if it's relevant but I found the following reference in an article written for the AHSA Journal by Barry Tate:
During the late 1960s in Western Australia Civil Flying Services provided two Beech Barons, on contract to the WA Forestry Department, for controlled aerial burning of the forests of Manjimup area south of Perth.
The article is illustrated with photos of VH-CFG but unfortunately the other Baron is not identified.
Rgds