Hello Paul,
This is the only line drawing I have of the Fiat A12 engine. Sorry it is so small.
I think the photo in your post is the Fiat A.12 displayed at the Research & Development Gallery, National Museum of the USAF. Dayton Ohio.
There may be another Fiat A.12 on display at the New England Air Museum, Bradley International Airport, Windsor Locks, CT
Are any of these near to you?
Mike