Lis, I understand that there is no definitive way to know what aircraft had what colors. The best we can do is try to understand what the manufacturer did, and when, as Dana Bell does in the link. Since the AZ Mustang has a "boxed-in" wheel well (much like Tamiya's quarter scale P-51), it would be best, in opinion, to paint it all Yellow Chromate, or Aluminum Lacquer. Since this is a B/C model, it may have still had the Lacquered (3 layers of protection) bay like your pictures, or due to the shortages and time crunches, may have been yellow chromate'd (one layer of protection), or a mix of yellow & green, and raw aluminum (as some spars may have been treated differently before assembly. It sounds silly to "split hairs" over any of these colors when there is no way to say definitively for each aircraft... π In that regard, I'd be willing to bet that no-one will nit-pick your selection, whatever that may be.
** I do see, however that your MkIII kit has the dorsal tail fillet, where-as some of your references for the "PK-J" airframe (and the decal sheet) show no fillet... That may or may not be easy to sand off and correct, just a heads up if you didn't catch that yet. π Happy building!
**EDIT: Nevermind that last bit.. I looked up the kit instructions and see that the fillet dorsal tail is an option, so no worries! If only I would have looked closer at the PLASTIC pieces in your first post... π
