Chuck, knowing your obvious passion for accuracy, I would like to point out that the P38 had a seam on the leading edge of the wing where the upper and lower skins met. I noticed this when walking around a real example. Perhaps there are pictures online of this. It is like the seam on the upper fuselage of the Me 109 in that is faint. It may have had filler in it during WW2, but I do not know for sure. By the way, the Spitfire had a seam in the same place on the wing.
I hope this helps. I really enjoy your work.
Don Schmidt