Don't quote me for NSW, but I do believe WA is similar, and all thats needed for registration here is to change the front indicator light lenses to clear and change the headlights to Australian spec which dip to the left (any 7" sealed beam should do, <$20 from supercheap or the like).
Of course, make sure she is roadworthy as well
Just to make sure call the RTA in case I've missed something.
Might be also a good idea to check out the best local Mustang forum as well for other good info and advice from a helpful bunch of guys
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