If you want it pretty then tape it at the very edges of the hood, and also put black on the visible lip below the front trim strip.
If you want it factory, then the black was first (dipped primer, not actually paint), and the body color was oversprayed around the edges. The amount of overspray varied widely by plant and by whomever was wielding the spray gun. I have seen where there was very little body color underneath except on the vertical surfaces on the reinforcement ribs that face the outside edge of the hood so caught a lot of overspray, and I have seen where it looks like an entire pass of the gun was shot under the edge of the hood. And on those with heavy overspray, it is generally not the same on all edges of the hood, so one edge can have a lot and another edge barely any.
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