I'm sorry SACO, I made a mistake.
The car in the puzzle is called in many different ways, and I do not know if it was restored with the specifics of a previous stage of its life (a Jap engine?). The configuration is closer to the last one and that was a 750, not 1100. Somewhere it is called Ficai-Jap, and here's the origin of my error...the original 1100 Jap was used in the 1st front-engined version. The 2nd, read engined had a Norton derived engine and 2 different bodyworks: the puzzle car is closest to the 3rd version, the one that had the custom built boxer engine.