I have a Deluxe Ash Mexican Fender Jazz, which I bought a few years ago; that was my first good quality bass after owning a cheap Ibanez for a long time. I'm finally getting around to upgrading my equipment. I bought a new amp recently, and I just ordered a vintage American Fender bridge and a new neck nut. Next I want to upgrade the pups and electronics, but I don't know too much about Jazz Bass pickup upgrades. What are some of the more popular options, and what exactly do I need to buy to upgrade all of that?