So manny options, but the route via Mt Gambier then the Glenelg-Hamilton Hwy is best IMHO . Can then go via the coast Great Ocean Rd to Geelong- Melb if you like the wind or inland to Hamilton-Ballarat-Melb, not as open as the main truck route that follows the Western Hwy via Bordertown which is the shortest route but harder on the nerves. Sounds like a great 5-7 day ride to look forward to, weather has been superb to date, hope it keeps up for you.😎