You're refering to "shade 16"?
Take a look at Page 55 onward in
http://www.dt.navy.mil/cnsm/docs/NAVSHIPS250-374.pdf
I know the publication date is well after the war but there is specific mention of:
"(B) Effectiveness and Suitability. This measure (formerly
listed in NavShips 250-631 as No. 32/3SSB) is applicable
to Fleet-type submarines. (Measure SS 27 F uses the newer
deck paint mixture; otherwise measure SS 27 F is identical to
32/3SSB.)"
Could "newer deck paint mixture" refer to an improved durability mix rather than a new color?
It sort of looks like achieving a shade by fading one paint color into another by spray gun technique. Feathering, if you will.
I also found this
http://www.steelnavy.com/images/chips/USNchip3.jpg Middle of second row
Tracy can probably be of more assistance.