I've started work on "Minnesota Mauler" so have been studying the available photos more closely and have come to some conclusions about the scheme:-
I suspect that both the nose art close up photos were taken at around the same time during the process of it being painted as neither of them show the large number 19 and all the group's NMF aircraft had these. The upper in-flight photo shows a similar mission tally to the lower nose art photo so it seems the large "19"s were painted on immediately after the second nose art photo was taken. These photos also show the lower nose below and behind the turret was painted white.
The second two in-flight photos were probably taken at a later date to the first one, as the stencil lines in the "19"s have been painted out. I'll skin it as per the upper photo though, as the mission tally is known.
I think Vraciu's suggestion about the red being over-exposed in the lower in-flight photo is likely correct. Looking carefully at this photo it is possible to see a reversal of the tone of tail markings between the in-shadow area just aft of the hinge line and the rest of the stab which is in sunlight. So in the shaded area the painted bits are darker than the NMF while in the lit areas this is reversed. Also the exhaust dirt on the top of the wings appears light in this photo while it is dark on the upper photo. Oil stains generally have a reddish tint so the same issue might be at play here. A less-likely alternative is lead in the fuel staining those areas white. So probably the tail codes were indeed red on 451st BG aircraft at this stage of the war.
I can't see any letter "J" on the rudders in these photos. While most photos of similar aircraft show a letter here there are a few that don't so I will leave these off.
I have a reference that shows the upper tail of 451st BG aircraft also carried tail codes, with the RH tail painted over and with a red circle on the LH tail. None of the B&W photos of NMF aircraft show these codes, but this may be down to the same issue of over-exposure of red hiding it. There is one photo of an OD aircraft called "Burma Bound" that shows these codes painted in white. The colour photo of aircraft "61" shows a red upper tail plane, but oddly this is the LH one and not the right. Hopefully Lyric1's new book will shed some more light on the tail codes of the group.
