Thanks to all who have shown and interest in the De Rosa I have been trying to ID. I wanted to let you know the mystery has been solved. Over the weekend I found the email contact info for Cristiano De Rosa (it is on their website , but it wasn't easy to find). I sent him a description of the bike and photos. Today I received the reply from him that his father, Ugo, had made the frame in 1972.
Unfortunately he did not say how he determined that or if the bike is a particular model.
Again, thanks for your interest.
Jamie