An interesting subject. I attempted to research this in connection with my web article on the Vitus 979 frame. This was indeed used as a "neutral" support machine, Tout Mavic equipped, c. 1982-87. But photos are hard to come by. Also Vitus/Mavic supplied the machines used by the Colombians in 1984 in their famous Dauphine Libere triumph as the team arrived in France without any equipment whatsoever.
I would be cautious of company contrived "displays" after the fact, too. My experience is that these are often the work of PR bright boys in their 20s rather than those actually familiar with what was used or folks grounded in the research skills to find out.
And time frame matters obviously in terms of what type of frames/components could have been used. Some of these photos show it all over the shop in terms of that. No one can possibly accept that Brooks leather saddles were used on neutral support machines in a professional road race for example. Well not one post 1965 at least. And that casts doubt on the whole effort frankly.
Anyway, the url for my article is
https://on-the-drops.blogspot.com/20...vitus-979.html
the bit on Mavic support machines is at the very end of the section on Vitus 979 equipped teams
Peter Kohler
Washington DC USA