New pickups in Jazz USA deluxe 5 ?

I just sent you a PM with a couple of thoughts and recommendations, but in general I would at least start with a set of replacement pickups that do not require mods. Once you play them and try them out, you may determine that you still want to go with MM bass. At that point, you would have to make irreversible mods to your bass, but at least you would have tried the jazz replacements first. I would hate to see you mod your bass, only to be potentially unhappy with the results, when a simple pickup swap would have done the trick!