It looks like you have this WWAAAYYYY under control, but can I suggest painting the the machanical "guts" parts and mechanical joints in a very dark grey -or- black?
This simple step will provide all of the shadow you will need in all of those millions of little nooks. Black or grey will also provide a strong foundation for any metal colors used for the "guts".
Just an idea, it will also save you many headaches when you apply washes to all of the many nooks in the mechanical areas.
Thank you all for your comments! Very nice.
My camera was not working until it repaired ,I painted. The basis has been chosen from the German yellow-olive, faded in the sun. Added to the wire in the head robot. the rest can be seen from the photographs.