Gorgeous work!! I wonder, if there were a larger European market for the OV-10, would the French government push a re-engining, replacing the T76s with TUrbomeca Astazou? These are the only two direct-drive turboprops in that power range (before electronic engine controls, this gave faster engine response than did the separate power turbine design of the PT6 and M601. I could see doing such a replacement since you'd only need to replace the front cowlings/intakes and the props as the Astazou used electric prop controls rather than the hydraulic ones used by the T76/TPE331 (FWIW, Mitsubishi went the other way with the prototype MU-2A using Astazous while the production Mu-2B variants have all used TPE331s.