I've got a FrankenFender of my own too! My Cash Convertor MIJ Jazz Bass is running a JPJ EMG setup. The pickups are closer together than Stu's tho'.
Running all of them together get's a wickedly tight, ultra-ballsey slap tone. Love playing that one, but it's a bitch to gig with. Heavy lump, that one.
As for P/J setups, I find those with reverse Ps are great for slapping! Tight bottom end, with really meaty top pops.