I respectfully beg to differ.
As a photographer I have to congrats you in your explanation about lighting, shadows and angles. I just feel bad about all the pickguard question, because I'd assume that looks original... sorry friends.
Since the pickguard is chamfered around its entire outer edge, the bottom layer would be equally visible around the entire pickguard, except where it meets the control plate. This is clearly not the case. Not only that, but if you look at the direction of the light source, it's obviously coming from the behind and above the camera lens. This is borne out by the position of the highlights on the body, and the cast shadow on the wall behind. The dark edges you refer to correspond exactly with the direction of the light source, revealing them as shadows. Finally, if you look at the enlarged section at the top left in the photo, you can clearly see the white bottom layer of the pickguard being reflected in the finish. With a black bottom layer and chamfered edges, this would not be possible.
Whether this is the original pickguard or not, I do not know. But the fact that our friend Marco is in possession of an original one that is in fact two-ply, it would seem fairly likely, given the fact that his bass and the one in the picture are of the same model year. I'm sure it would be possible to find out for sure whether two-ply pickguards were standard and what model years had them by asking on the Ernie Ball forums.
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