Perth is a long way away when you look at a Map and think about driving there in your Moke, however daunting it may seem though you may be surprised to find that the majority of Mokes could be driven there tomorrow if you wanted too. However some attention to preparing your Moke for such a journey can mean the difference of getting there and back with little more than an oil change or spending your whole trip doing running repairs and limping into the next service or town. Like anything preparation is paramount.
The first thing to remember in preparing your Moke is don't take your problems with you, fix the known issues before you go and avoid a lot of time playing in the dirt on the side of the road. Have a mechanic or knowledgeable friend help you over your Moke and check for the little issues that might become big ones after a few thousand km's on the road.
Second thing is to make sure you have given the Moke a good service and tune before you leave and do take the time to go for a drive for a day with your Moke full loaded as you would expect to be on the actual trip. This gives you a chance to notice small things that you might not notice in normal daily driving, things like the temperature rising on the hills and suspension going bang on bumps that have never concerned it before. Once in a group it becomes more difficult to stop and fix those little issues without holding everyone up.
Thirdly there are a number of small modifications or improvements you can make to your Moke that should a few known problems occur to your Moke they can be a minor inconveniences rather than a major roadside issue. You don't need to carry enough spares to account for every possible issue, but just having the basics with you saves the need to borrow or being stranded without that simple item that could take days to freight in.
Finally, just as important about making sure your Moke is mechanically ready for the journey is the need to make sure it is comfortable for you to spend up to 3 or 4 weeks in your Mokes. A little rattle or flapping canopy that you put up with in a day of driving will have you bouncing off padded walls after a few days of Moking and you will be looking for a razor blade by week two.