Just got this Bartolini pickup and NBMT off of Ebay for my Modulus Sweetspot. It came out of a '93 Sweetspot. Anybody know for sure what the switch is for? The owner seems to think it might be a coil tap, but I'm thinking either active/passive switch or mid frequency selector. I'm hoping to use this in conjunction with a Bartolini MBP and ABM piezo bridge. I'm also hoping to be able to run 18v instead of 9. Anybody know for sure if it's feasible?