I think the new MIA Fender Jazz Basses are coming with a built-in series/parallel switch. It's on the neck volume knob, but it's not a push/pull. It's actually a button on top of the knob. Have you guys seen these yet? Post a pic if you can find one. I've been thinking about moding my Jazz with a series/parallel switch and this is a pretty slick looking way to do it.