It will be stamped on a machined smooth spot. This is usually where the rear end cover is bolted, it will have a wide point that the cover isn't covering and the number is right there. Often it's on a machined area between the axle tube and the rear cover. If it's a drop in pumpkin like a 9" they are on the front on a machined area on the cast third member.
But on that Camaro I seem to remember a triangular tag.