The Australian Rally Championship was inaugurated in 1968 and comprised events from each state. Victoria has hosted one, and sometimes two or three rounds of the ARC in most years. Victorian crews have won the ARC about twenty times over its long history.
The ARC was originally limited to vehicles complying with CAMS Group C Touring Car regulations but in the late 1970s this was relaxed to include the more heavily modified Group G cars. In 1982 FIA Group A was introduced alongside CAMS Group G, with some interesting outcomes! By the end of the 1980s the ARC had fully adopted FIA Group A, Group N and later developments.
The original ARC scoring was 9-6-4-3-2-1 for the first six (eligible) placing in each round. The scoring was changed to 20-15-12-10-9-8-7-6-5-4-3-2-1 in 1981, but still for each complete round. For several years when Group G was running in parallel with Group A, points were awarded to both vehicle categories. In the 1990s there were several years where crews could also gain half points for placings in a limited number of state championship events. A more complex scoring system was introduced some years later, awarding points from 40 down to 1 for the top 20 places in each heat of a round, with various loadings, bonus and power stage points.
Tom Snooks has written a detailed history of the ARC from 1968 to 1988 inclusive. You can read it here.