Mark,
Yes sorry, I did know it was from the Princess, it was just a friend of mine said that it was common practice to upgrade from the Cortina's original 2 pots to the 4-pots from the Princess.
I have seen kits availible for not a great deal of money which include the 4-Pot callipers, Spacers & Vented discs. If I ever decide to go down the performance engine route this may be somthing I would consider.
To be honnest my DMC brakes are pretty sharp anyway.
James