“Certainly (figure 1) gives no indication of white stripes on the leading edge of the tailplane, and the appearance of a white "stripe" on the near wing is probably an unfortunate combination of the red-doped gun ports on the wing leading edge (just outboard of the u/c leg) and some sort of (exhaust? spilt fuel?) staining. The lighter area visible is definitely not in the standard location for the white stripe seen on British-based Mustangs.”
I'm not buying the dope portion, the red in the roundels is very dark in the image.
A fuel spill eating through the paint? maybe. The problem is that spilled fuel should flow down to the rear if spilled. so barring some fool spraying fuel forward/up the wing and it removing paint on the gear door perfectly perpendicular to the direction it would flow off the wing - and also almost perfectly in line with the inboard edge of the removed paint on the wing with the door closed.
Sorry. That's a white painted stripe in my mind.