Alex, you're right
Sydney FC 67956 S
Melbourne FC 64940 M
Brisbane FC 26872 B
Adelaide FC 18971 A
Perth FC 15305 P
Very hard to tell the youngest car, the only one I have complete details of is the Vic car which was registered on 30/12/1959 and has engine number L638544
All the other car details are incomplete with no engine number details provided. The Sydney and Brisbane cars have unknown owners and , the Adelaide car is a wreck in the Barossa yard and the Perth car was for sale.
The highest engine number I have recorded is L638747 which is in a ute, but it is not the original engine for that vehicle. This could very well be an engine from an early 1960 car. I have 2 other engine numbers recorded above L638544, one is in a spec wagon and the other in a ute. Both these vehicles have a lower
chassis number than the sedan so would date older than it.
Not much more detail unfortunately
Ken