Airplane tubing? Nice! I'd say anywhere between 1999 and 2011, The one (Rabobank) I used to ride was a 2000 edition and was built exactly the same. My dad rides it now so I don't have it at hand to check the numbers. Will have a peek when I'm at my parents' place.
btw There's a 'Colnago Official' Facebook group nowadays, maybe you can shoot some pics their way
Yes, Airplane tubing! Thnx for the info Peet!!