A lot of it will come together at the end,.. when you use white to trim out your "hard edges". It will give the eye reference as to areas of "gathered light",.. and really helps sell the illusion of reflectivity. In this case,.. I'd say to imagine a light source (like the sun), and trim your upper edges (and possibly side edges) that face the light source,.. but not on the lower or far edges. Because light does not collect on every edge,.. even on chrome. And the inter-play of light and shadow is what you need here.
Hope that made sense,..