I just found a whole heap of glorious videos of the Nullarbor area and other parts of southern Australia.
So many memories for me - https://www.youtube.com/channel/UCDM9B3S8nquCLHETDrETaDg/videos
A really really long ‘short cut’ - very straight, and a pretty drive:
https://www.bbc.com/travel/article/20220613-the-outback-way-is-this-the-worlds-emptiest-road
"Sure", you say. "I've been to England and a few of the other former British colonies. I've driven on the left side of the road. I know what it's all about."
The last sentence in this article sums up the situation perfectly:
'(Changing the side of the road from where you usually drive) ... may sound intimidating, but not to worry: it's surprisingly easy to switch sides, as long as you're careful and take your time on the road.'
I'll add one word to 'being careful' and 'taking your time on the road' .. and that's concentrate - especially if you're travelling in an area where there's not much traffic.
Driving on Australian roads is not scary: for the most part, you have the other traffic to guide you. It's when you get off the beaten track and go into country areas that you need to have your wits about you. Even though you're sitting on the right-hand-side of the vehicle, it is all too easy to let instinct take over.
(I knew a young American bloke, who was in Australia to study at university, and bought a car while he was here. He was driving home from an evening at a friend's home one night when he went through an intersection where there were no traffic lights. He was lucky to survive after being hit by a car coming through from his right. The impact spun his car around so much that the only panel left undamaged was the roof!
What happened? Instinct took over as he reached the intersection. He looked to the left (as you would in the US), and not seeing any traffic, kept driving through the intersection. Unfortunately, there was someone coming though on his right. Traffic on your right has the right of way.)
The above, notwithstanding, don't be afraid to drive on Australian roads. It's a great way to see the country.
Another tip: if you're planning to take a driving holiday, then allow some time to get some driver training in. The training will go a long way to settling your fears. There are seven state-based motoring associations -
the NRMA in New South Wales;
RACV in Victoria;
RACQ in Queensland;
RACT in Tasmania;
RAA in South Australia;
RAC in Western Australia; and
the AANT in the Northern Territory.
Each of these organisations will explain our road rules, and they sell excellent maps - not only of their own state, but of the other states as well.
Google Maps might be good in the cities, but you may well be out of phone range when you drive in the country.