I'm rewiring my Fernandes Ravelle with a set of Gibby humbuckers, I'm told they are a 490 and a 498. All went well as I used the trusty Seymour Duncan diagram like usual, but I see that my 3 way LP style toggle has 5 wires.. one for each pickup, a ground, one that goes to the jack,, and a bare wire which I don't know what to do with.. I don't remeber where it was soldered to originally as I've changed the pickups out of it once before without a problem. It wouldn't bother me but when I turn the gain up on my amp I get this screeching feedback when I'm not playing and I wonder if it has anything to do with the 3 way and a grounding issue. If I switch guitars there is no feedback.. any ideas?? only other thing I can think of is that the pickups are not potted,, but I would think that newer high end gibby pickups would be.