I'm looking to change the pups on my Yammy fretless,(P/J passive set up), I want as much growl as poss', not bothered if active or passive. I have looked at other fretlesses but none appealed. Although the yammy was really cheap,£150, it plays and feels really nice. The fingerboard is Ebony. I have never had the need to change pups before, so any help would be appreciated.