It was certainly painted in situ on my car and has been on most of the seemingly unrestored cars I've seen. I've also been told the same by a couple of long-standing members of the club. Unfortunately all the early factory photos are in black & white, but if you look at these enlargements of painted cars coming off the production line, you can see the black rubber around the windscreen stands out, whereas the strip beneath which runs between the windscreen frame and the body doesn't. The B&W photo of a restored car with the strip unpainted hopefully illustrates the difference. Other factory photos show the cars with the bodywork (minus windscreen glass) fully assembled but unpainted, and I can't imagine Sharp's doing this only to have to take them apart again.