I have installed a Seymour Duncan SPB-3 in my cheapo P-Bass knockoff. When I touch the pickup screw closest to the control cavity, it clicks loudly through the amp (a grounding issue, I guess). It only does this when the pickguard is installed; if I remove it and move the pickguard away from the pickup, it stops. This is not really a problem when I play pizzicato, but when I slap, it sounds like I have a bowl of rice crispies in my amp. In fact, I don't even have to touch the screw when I'm slapping to make this happen; moving my hand in close proximity to the screw is apparently enough to make this happen.