In lieu of a traditional pickup selector switch, many guitars have individual On/Off switches for each pickup. That can potentially allow greater control and newer options (e.g., all three pickups turned on at same time), but there's a trade off in that this is almost never as fast as employing a single switch to select combinations of pickups.
However, this approach merges the idea of On/Off switches with coil taps... all in one mod! By using an On/Off/On DPDT, you get to have both humbucking and coil tapped mode with the "off" option in the middle position.
Note: This mod will work on guitars that *do* have a pickup selector switch, but either the "Off" option or the pickup selector will be redundant. Of course, you could always bypass the pickup selector switch and wire the DPDTs directly to the output. The selector would then be just for show,
*For more exposition on the various types of switches (including the different DPDTs), see the appropriate section on the switches page.
How
it's done
Of course, you will need an On/Off/On DPDT switch for this mod. And it's all wired together as shown. As usual, the colors of the wires depend on those of pickup manufacturer. Consult the paperwork that came with your guitar, the manufacturer's website, or see this page. In this diagram, the red wire is the output from the pickup.
