Make sure you are turning the phillips screw the right way- if you screw clockwise the pickup will rise if you screw anti clockwise the pickup should drop nearer the scratchplate. Under the scratchplate there is a spring or possibly a rubber sleeve between the scratchplate and the base of the pickup. Turning the screw clockwise compresses the spring and therefore RAISES the height above the scratchplate. Doing the reverse LOWERS the pickup.
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