Denis, so darned interesting...Wyss's book "Detomaso Automobiles" shows another prototype, very much like The prototype but with vent screens below the rear glass---(still with external hinges, and not the Fiat 850 tail lights, full rear bumper...Maybe just a re-do of the hatches on the original proto?
And looking closely at what I thought was a shadow, but appears that the Automobile Quarterly and Sports Car graphics car shows the removable roof section---painted body color, not glass---as does the Provamo picture set of "502". Are there any pictures that show the dash (esp, the "10 gauge" layout) in the Sports Graphic?
I see your research that the Red car was sold back to DeTomaso. Was this the first real Mangusta?