[prydey]

Bought a car from a dealer in nsw many years back and drove it back to Adelaide. The dealer got me to follow him around to a mechanic mate of his, who did the paperwork that was required to get a permit to drive it home.

As mentioned by CB, they are quite strict on the duration and give you the bare minimum to get to the relevant registration place in your home state. They were only going to give me 1 day and I had to explain to them the logistics of driving back to Adelaide and the fact that the nearest dept of transport inspection facility only operated Wednesday and Thursday.

So yes, be clear with your plan as well.