If you keep your car road registered different rules apply.
No need for a catch tank or a blue triangle. Tow hooks are optional (I just fit the front one). 4 point harness on a standard seat is a great improvement. Try before you buy a new seat. A non ADR seat will give you problems on the road.
Start with a bonnet strap and a fire extinguisher. Put the car on the track. If you are a couple of seconds slower than others in your class then you will pick this up with driving technique. If you are 10 seconds slower then maybe spend come money on the car. If you are 15 seconds slower then just drive for fun. Prize values are 1st place $10, second place $6 and 3rd place $3.50.
write this on a post-it note and place on the drivers sun visor. Read it every time you line up on the starting grid.
got to cams.com.au for more details.