Have just realised what you said John. Don't be misled by the button numbers only being 1 - 6, follow the instructions below and it will work:
Entering a Ford Radio Code
Keep pressing button 1 until the first digit of the code is displayed,
then button 2 for the second digit,
then button 3 for the third digit,
then button 4 for the fourth digit,
then press button 5 and hold for a few seconds to enter and store the code.
Hope that helps.
Bigh
February 2010