The following year, Gregory teamed up with the man who was to become 1970 Formula One World Champion, Austrian Jochen Rindt, and the pair won the race in a North American Racing Team Ferrari 250 LM.
Ao ano seguinte, Gregory uniuse ao home que se convertería no Campionato Mundial de Fórmula 1 de 1970, o austríaco Jochen Rindt, e a parella gañou a carreira nun North American Racing Team Ferrari 250 LM.