From what I am told, they bought a Gordini (remember no such thing as an R10 Gordini) in South America, or Mexico as they were made over there too. It was then dismantled and the mechanical bits which differed from a standard car were brought in, and assembled into a standard shell. It would not (probably) have the G strengthening bits in the shell, although they are possible to replicate. I believe it's a 1255cc 5 speed, 4 rear shock version.
Now, John, stop spending so much time on here and get out into the shed and work on the car.