Mine has plastic unpainted quarter bumpers like a 1600i & i believe the 1600i grille is correct ( mine had a series 1 on it but i believe it was changed to look more normal).
Mine is not a Diana car, but possibly royal , although as said no concrete proof , it is a genuine from the factory black car.There are pics in the rallye news of the car in the barn where it was stored since 93, i will be taking some pics next week.Thanks.