I will quote a post by Dana Bell from Britmodeller forum about this early configuration:
"Those 1939/40 designs were the first to carry internally mounted 50-calibre wing guns, and no one was quite sure how to minimize the drag along the wings' leading edges. They all had blast tubes extending from the barrels, but until the NACA reports came in there were many variations. Clearly, flush-with-the-leading-edge was not the best, since the blast tubes were quickly extended in production."
I believe this was also one of the many "anti-freeze" measures, but employed at the Aleutian bases exclusively.
Sooo, I guess that my model probably should have guns taped-over, and only dilemma is the exact color of this tape.
Sure wasn't white, as in my previous post, as that would stick out in the photos.
Regards,
Aleksandar