Changing the stock pick ups and preamp on my fender jazz deluxe v to Aguilar J60's and a Nordy 4b3a. The Nordy is 9v stock preamp is 18v. Can I use the Nordy as 18v? If not, do I have to clip one 18v cap or just leave it empty? I want to still use the battery cavity in the back. TIA!