The impossible hour is the 70's attempt, the black and white pic is the 68 record.
Interesting stuff about the 68 bike if it's not just hype. By about 1983-4 nearly all the top level TT and pursuit bikes had things that were different from normal bikes. Aero tubes, narrow hubs, often weird headsets, and usually special handlebars. Not really modifications, since they were built that way. 1968 would be very early for aero touches like that, but if it would have been done anywhere it would have been an hour record bike.
Which brings me back to the black and white pics of the 1968 record. Is the
bike in the pics even a Cinelli?
The front view shows a headtube logo that doesn't seem to be the Cinelli
logo, at least to me.
In the side view here
http://www.cykelsiderne.net/
Steve Birmingham
Lowell, Massachusetts
USA