unmarked cars i notice more then marked cars.
holden commodores have a switch in their grill for their lights for external switch off. also a foghorn sitting under the grill in the air intake. all running fe2 suspension unless their drug squad or investigator d's in sydney.
au falcons, easy to notice, way to easy. suspension, no caps (same as como)
unmarked highway patrol
ss commodores have 3 aerials places on the top of their windscreen on the back of the car.
xr8's have either 3 aerials but most commonly have to short 30 degree angle pointing aerials on the right corner of their boot.
I think your to paranoid
In sydney we have a hell of a lot more modified cars in perth, in a falcon you dont stand out at all, police dont even look at you, and i speak from experience from having a rice burning modified honda. i get picked on all the time in that, but never in my falcon.
Have fun, do crazy things, how many people run NOS on the streets? including in perth. :0
exhaust flames? pfft, off a switch, u'd never get caught unless you became stupid man :)