Replicating Forza's default light and dark silver paints

I noticed that with as several manufacturers, Forza provides these lovely light an dark silver metallic paints (for example, with the Audi R8, the MP4-12C and pretty much all the Mercedes).

I'd like to replicate this paint for my RUF, which doesn't come with this silver paint, but am not sure how to begin. Forza 5 lacks the metallic paint option, and I've tried using twin-color flakes, but it doesn't look as good as the default metallic paints they provide.

Has anyone had success replicating these default silver paints? Thanks!

 

Have you tried using the color shift paint option? The Metal flake can look odd at times, and the flakes seem a bit to big. I feel color shift is much smoother.

 

Oddly, this is where GT's paint chips could be a GOOD thing.