walk way painting

I myself would not paint the walkways a metallic color. You might want to go to your local bookstore and check out the magazine rack for an issue of " Airliners ". I have many issues from past and present and find this publication to be one of the best for anyone interested in the airline industry. Many many color photos of various airlines and good articles and stories related to everything concerning the airline industry. I'm sure with all the color photos in this publication it will be just want your looking for as far as color references go. Check it out.

Did either have wing walk ways?  I didnt see any on Delta 732 and Alitalia 742 searching through anet. Could you post a pics with either showing walk ways?

The walk way area I'm refering to is the middle large  area of the wing behind the leading edge and infront of the flaps maybe this is a better way of putting it.

That would be the inspar Corogard.  Its pretty much a anti corrosive that can be tinted many colors including the clear, boeing and airbus greys we commonly see on inspar panels, and maybe be mistaken as a solid painted wing.  As far as the dark/silver metallic theres decals for it, Xtracolor has it in their range or just use a flat dark silver metallic. 

    If you are refering to the area between the slats and the spoilers, Delta aircraft were a flat silver color. If you are talking about the overwing emergence exit walkways, Delta aircraft were painted flat black with a Back and white border stripe. The emergency exit walkways had crushed walnut shell mixed into the paint to make it non-skid.