I have a Fender Fretless Jazz Bass(Mexico) purchased in 2010. I'd like to get some more punch out of it. I've put flat wounds on it which have helped considerably but I'm still looking for that pure butter sound. Would different pickups help me? I've been looking at the Fender Custom Shop '60s Jazz Bass Pickups. I play through a GK 800RB with 4-10 Cabinet, also an Ampeg B-15 Flip Top...........Thanks, Bill