No such thing as the RTA in QLD :p
Changing from one OEM option to another can be done without a mod plate on any vehicle (in QLD), it has nothing to do with the age of the vehicle.
e.g. you can fit a mitsubishi cordia turbo engine into an na cordia if you upgrade the brakes and suspension to the same spec as the turbo model.
So for any SIIA, you don't need a mod plate to fit any optional engine, but you would need a mod plate to fit an engine that wasn't originally fitted to a SIIA.

