I realized that I forgot one thing: the case feet!
I previously cutted and painted in grey 8 wood discs:
To make a “metal” effect, I sprayed a little quantity of white paint. It was just the quantity to obtain little white dots on the grey background, so these drops seems like light reflections, as in a raw metal surface.
This is the effect:
This is the sequence:
First the grey backround:
Then the quick pass with white spray, to form the little white dots:
I glue the felt pads:
And this is the result: