72 center cap colors?

I'm trying to restore a set of 72+ chrysler rallye wheels (is it rallye? ralley? rally?). Anyway I'm finding different looks when it comes to the center caps. Is the top of the cap and the outer rim chrome, while the inside is argent silver? Or is it just supposed to be stainless steel on the inside? I've also seen the inside around the lugs dark like the late 60's wheels but I'm not sure. I'm just trying to make them look original again.