rear indicators

Need some help. Waiting for my 67 GTO to be shipped to Australia. While this is happening I am doing some homework as to what needs to be done to the car to get it registered in Aust.
One thing that must be done is to have the rear indicators flashing in orange (not red as in the USA)
My question, Is the rear indicator bulb a separate bulb with its own separate wire. If it is then I can isolate it and convert one of the four rear lenses using an orange lense grafted from another car.
But if its part of the tail/stop light wiring then its going to be a lot harder.
Any suggestions?????

I believe each lamp has two signal/brake light lamps on each side. These are twin element bulbs #1157 with the common ground. The other circuit is for the running lights. European lights have a different circuit for turn signal function and brake lights. The 67 GTO, as many other cars in the US share the same circuitry. I don't how you're going to be able to segregate the two circuits unless you custom wire the turn signal switch in the steering column, or better yet isolate the brake light circuit. I've got a better idea. Don't ship the car down under. Instead, move to the US and enjoy your car as it is.