RE: the Great Pink debate (or not)
My Grandfather flew P-40s with the 64th FS in Africa. He told me that the paint did indeed develop a very slight pinkish hue as it weathered in the sun. But it was slight, not ridiculously pink like Sue Parish's bird. And it was sort-of mottled, not uniform across the aircraft. The thing is: color is very subjective. For instance, it is known that people with light blue eyes are more sensitive to light, so colors probably looks a little different too. I think opinions differ on this pink debate, even amongst those who were there.
If you decide you want some pink, then I would recommend that after your base coat of tan is down, that you add mix just a little pink into your tan and apply to a few spots, rather like if you were doing german mottled camo. Then spray on your dark olive/brown camo blotches color over the mottled tan.