I have Gibson LP SL Special with a Bill Lawrence L-500L in the bridge - I got this one from Bill, and I have a L-500R in the neck - this one is the BL USA pickup with that written on it. My first question is: How different are the BL USA pickups different from the actual ones you get from Bill directly? Are there big tonal differences? My second question is: I want to install push/pull pots for both pickups. What pots would you recommend? Thanks!