I've been looking at the different vintage Gibson pickguard configurations from the teens to the 20s. The earlier ones are pinned twice to the side of the fingerboard, attached to the side clamp with two screws, with a pin going into a hole in the non-adjustable bridge.
The later ones have just one pin into the side of the fingerboard, a single bolt attaching to the pickguard clamp (leaving two redundant holes), and not pinned at all to the bridge (which has now become adjustable).
This would seem a lot less stable. I wonder what the reasoning was for the changes?
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