Actually found a picture that gives me a little more info on the paint. It almost seems like the fairing is all yellow. Which would mean I need to make my bands a little wider.
(Image removed from quote.)
This picture appears to have the yellow strip as big as the fairing with maybe the very base of where yellow meets black is painted black. It looks like the turret itself isn't fully painted BUT has a blk/y/blk strip itself. Almost looks like it's in a ^ shape, with the tip pointed to the guns. When you look at this picture and the first ones that you posted, the 2 black stripes appears to match in thickness, but the 2nd stripe too far from the horizontal stabilizers which is likely because the yellow stripe looks too thin. In other words, the yellow stripe is the only stripe that looks like it needs to be made thicker, pushing the 2nd blk stripe closer to the horizontal stabilizers. As for the turret itself, if you can just get the fairing worked out, you could probably get away with leaving the turret bare, if that is possible.
EDIT: Also, I don't see a black stripe on the front edge of the vertical stabilizer in the historic photo while yours has it. Is that part of the plane or are you using another photo?
I just noticed something between the two pictures, the turret on OUR B-29 is bigger than on the one in the picture. The turret is still intact, as you can see the guns pointed straight down... This may be a reason why it's harder to get the stripes to look right.