They didn't come with instructions? The bevel side goes up, no matter which ring goes where. If there's a dot on the ring, that too, goes up. Some sets have different top and 2nd rings, some don't. But they're usually marked in their packaging as to where and how they're installed if there's no instructions. Plain black iron rings aren't specific to the groove, unless the two are different thicknesses. Moly faced ring sets, the moly ring goes in the top groove. The key there is that the ring has a moly filled groove in the face that goes against the bore, it's not a moly-alloy ring. With a close visual inspection you will be able to see the moly in the groove.