[Buckeye30]

Hi James the red was removed from the insigniae (stars and rudders) from May 15 1942 ( ALNAV Dispatch 062230); at Midway in June the wings had 4-position insigniae and no rudder stripes.
From Feb. 1 1943 the insignia was deleted from upper right and lower left wings ( Spec. SR.2c 5.1.43); and standardised March 1 ( A-N Spec.AN-1-9). It also specified a mix of white and Light Gray for the upper insignia star.

If you want to do the later 1943 style, the bars were added June 29 ( A-N Spec.AN-1-9a); at first with red outlines , replaced by insignia blue Aug. 14 (on aircraft in production) (A-N Spec.AN-1-9b) .
On aircraft in service Sept. 14 (ALNAV Dispatch 164). Still to have light gray in upper wing insigniae.

On Sept. 28 1943 , ANA Bulletin 157 co-ordinated colours for the USN-USMC-AAF and British requirements as regards Lend-Lease ( including many naval aircraft).
Identification on these observation planes was usually plain black numbers without role designation as in these photos.
The 4-colour scheme ( Non-Specular Sea Blue, Semi-Gloss Sea Blue, NS Intermediate Blue and NS Insignia White) was introduced Jan. 5 1943 ( effective Feb. 1 ) ( Spec. SR-2c). No doubt the Blue-Gray/ Light Gray scheme continued for some time especially on catapult aircraft.

Regards Nick