BTW, straight from the WOF manual.
I dont know if the plates and tags have been swapped from the iS onto the iA body as this thread hasnt made this clear, but if they have the above would confirm it is illegal unless done by an authorised person.
I know someone brought up the Dakar M3 that was rebodied; the difference with the was that it was still a 318i, the tags had not been swapped, but it had been certified for all modifications (which is legal).
If youre swapping plates and tags from one car to another; no matter what the car is, or what your reasons are, unless its done legally you are no better than young Johnny with his totes wikd dirft Cefiro.