Leading Edge Slat underside color for SB2C-4 Helldiver

I'm not sure I can give you a definitive answer, but my first thought was perhaps those slat undersides might have been painted green zinc chromate, or perhaps the yellow chromate. I found another modeler's build of this kit, and it appears this person went with the green chromate.

http://hyperscale.com/features/2002/images/sb2cpc_15.jpg

This is just one modeler's interpretation.

Another that I found in this next link, read to where he talks about lack of actual color photos; he goes with dark sea blue.

http://web.ipmsusa3.org/content/sb2c-4-helldiver-0

If I was doing one of these (and I have one in my stash), I would likely opt for the zinc chromate green if for no other reason to break up the potentially monotonous dark sea blue.

There is ONE flying full scale Helldiver in the U.S. It is being operated by the Commemorative Air Force if I recall correctly. I saw it a few years ago at an air show and do not or cannot remember seeing the underside of the slats. You might try contacting them and ask this question. My experience with them is that they are very cooperative with such requests for information, AND they make a unsurpassed effort to be accurate in their restoration of these historic aircraft.

Standard USN practice of painting was to paint areas visible when stowed on deck to match the surrounding exterior colors. If the slats would drop while the aircraft was stowed on the fight deck, they would likely be painted to match the upper wings. The wingfold interiors were usually in Intermediate Blue on three color schemes and Sea Blue on overall Sea Blue schemes.