Not wishing to argue, but I was told the cut off date for the old style plates was for cars registered before October '73. This was when I had my plates made for my VW Camper..... but that was years ago and i may be talking rubbish, but thats what the plate maker told me.
There are also several Mk2 Golf Gti owners in my area who seem to be hassle free running Black and Silver plates on D, G and H plates, one of which is in German size and style letters and numbers.
Each to their own I suppose!