I have a three pickup SG (a "Gibbo" copy). It has three humbuckers. The Neck and Bridge have their volume and tone controlled as on a two pickup SG (ie each has its own volume and tone); the toggle switch also works like on a two pickup. The Centre pickup is turned on via a push/pull pot; there is no volume or tone control for this pickup. The volume of the centre pickup is a little less than the other two (at full), but it blends in well, and I'm very happy with the sound. My query comes about swapping the pickups and advice on how to make sure they all match. I'm not as happy with the Neck pickup as the other two, and so would like to swap it out, but obviously it's replacement has to fit with the other two and not swamp out the centre one. Any advice on matching in a third pickup please?