I've got an old EB-0 with the Gibson equivalent of that pickup- polepieces are in the center. Anyway, when I was 16 I routed out a cavity for P pickups, since then it's been really hammered. I decided to try moving the pickup back closer to the bridge, and just enlarged the cavity I had for the other 2 sets of pickups in it. It didn't sound good there either. Granted, it's an EB-0- mahogany, set neck, but I'd imagine you'd get the same results. An EB-4 is pretty much the same, but I've never played one of those. I don't know if Fender was going after people that wanted to be Felix Pappalardi or Andy Fraser- after all this is about the time when they were big, and both playing those massive humbuckered basses. In fact, Gibson re-issued the EB-1 because of Pappalardi.