Thanks Guys.
I have a knight in shining armour that has come to my aid.
I'm very lucky to have the best Morgan Dealer in the Country just 3 miles down the road.
It is a case of recoding the speedo and its also true that the mileage would have been affected.
Philippo......Interested to know how you managed to find the right numbers to input to match it to your sat nav.
lee