I would doubt the Grandé ever got a Mach 1 grill. Not sure about 1971, but for 1972 and 1973 Grandes, they got unique wheel covers as standard equipment. Grandes and Mach 1's were only body types that got color-keyed dual racing mirrors as standard equipment.
Most Grandes did come with a thin Grandé-only side tape stripe running along the top of bodyline. The exterior color designated these stripe colors.
You rarely see those stripes as many aren't aware they came that way. Notice some of the 'GLOW" exterior colors did not receive these small stripes.
Here are the related stripe color combos from the final revision of the 72 Dealer facts Book:
Ray
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