The switching is done by using a push/pull pot. Or you can use a push/push pot(which I dont recommend). There is a major difference in the tone with the coil tap and the series/parallel wiring. Especially with the pups that I chose. Tims really recommended coil tapping the warpig and now I know why. In tap mode, the warpig in the lead channel takes on a very hot single coil pup. Hot enough to still get some serious bottom end. In clean, is has a very bright, glassy tone. The cold sweat in parallel mode is very thin and glassy. I love it. Very bluesy. Using both pups with both in the tap and parallel mode, I swear you can get a Les Paul to sound very close to a Fender. Tone that would make Stevie Ray very proud. I highly recommend this setup if this is something that you are trying to achieve. :D