GUN PORT TAPE
Actually it seems that the red covering over the gun ports was doped on fabric. Apparently done for each flight. To UV map that onto the wing surfaces (top/bottom) with Cinema 4d took 16 rectangles of red. Each had to be positioned along the length of the wing as well as fore/aft and angled tangent to the leading edge. They all have to "line up". In PhotoShop (where the texture resides) that took a lot of layers. Next problem was to make a version where the covering has been blown away when the guns fire. I did that with a ragged brush and trial and error bouncing back and forth from PhotoShop to C4D and back again ... over and over and over. I did all of that painting on one layer on top of the others so making the layer visible or invisible make an un-fired and fired version of the coverings. Now, I am sure there must be a better way but I am struggling with the "sharp angle" that results at the leading edge of the wing as well as the top and bottom of the fuselage. It may be that more lines have to be added to both. It is also disconcerting that the UV mapping is fine until a subdivision surface is added to the wing at which point a stripe at the trailing edge on both the top and bottom is generated. HUH? I don't have a clue about that. At any rate here is what the "after-firing-the-guns" version of the leading edge looks like. All of the previous Spitfire images did NOT have the guns positioned properly and the guns would have shot up the propeller. They are now positioned to the 3-view drawings. There sure is a lot of weight away from the roll axis and the guns would have a lot of "parallax" out at 400 yards so I am sure they had to be bore sighted or the "spread" could have been rather large. That technology and procedure must be interesting. Today, just like in about '48 when I built a stick-and-paper model of one of these things, the asymmetry of that one "Lucas refrigerator" hanging under the right wing amazes me.
I have included the "texture map". I simply copied the UV map representation from C4D into PhotoShop and did the painting on layers. Not the easiest thing in the world to do.
WING UV TEXTURE