She's looking Uber Cool Jim.
As Pat mentions above, Prova-MO XX were effectively what in the UK, we refer to as Trade Plates, allowing the cars to be temporarily driven on the roads around the factory without actually being properly road-registered. 'Prova' (Test), 'MO' (Modena), the issuing office.
Jim, when you do take that beauty for a run, I hope you get some footage for us all to drool over!!!
Best
Mark