I think I have the same (or a simlar) book. It dates from the late 60s/early 70s, when research of Japanese colors and markings was still in its infancy. Many reports from witnesses described the Pearl Harbor attackers as being "golden" or even "yellow" colors. Research indicates that the Vals and Zeros were painted a tannish-gray (the exact color is still the subject of some debate) which could have looked yellowish in the morning sun.
As mentioned above, overall yellow-orange was the standard color used by both the Japanese Army and Navy for experimental, prototype, and training aircraft (the shade used by the Army tended to be more yellow than the Navy color.) As attacks on airfields in the Home Islands intensified later in the war, many trainers and experimentals were given a coat of dark green on the upper surfaces.
The Val model shown above represents a squadron commander's aircraft that had orange sides for recognition. Unfortunately no photos of it exist, just verbal descriptions. I've seen it interpreted as a solid coat of orange, or various flame-like patterns.
Many of the Kates (and a few Vals) received some camouflage on the upper surfaces en route to Hawaii..various combinations of greens and browns, some blotched and some solid colors. Since they were painted individually by the maintenance crews, there wasn't any set standard. Some were apparently painted with deck mops.
Among us modellers, the recommended shades for the "gray" color are either Floquil "Concrete" or Gunze Sanyo's interpretation of Luftwaffe RLM 02 "gray green." I used the latter color on this Pearl Harbor Zero a few years ago..

SN