Hi,
I've seen both body color and argent. I think more argent then body color. It's a tough question because I know the 69 fury did both. Mine is argent from factory on a sport fury but I've seen sport furys with body color panel also. In the 69 fury brochure, all cars have body color including the sport fury which is the same color as mine. Consistency in this era was sketchy at best so I'm guessing you could get away with either for whichever you prefer and it would be correct. Maybe it was by plant.