I installed the Dimarzio Js in my GL last weekend. The old pickups seemed weak, and so far I like the Dimarzios. I had some grounding issues initially. The wiring diagram doesn't say anything about all these grounding wires coming from various places - the two copper plates under the pickups, and then one from the bridge. Mostly I just tried to replicate what was there before, but when I was done, I had a hum that went away when I touched the control plate. My output jack didn't have anything connected to its ground connector, so I ran a wire from that to the ground and the hum vanished, but it seemed like an odd thing for me to have to do, given that it wasn't that way originally.
