Wiring for a new XZ Steinberger

Hey fellow bassist.
Just got a new Steinberger XZ and I was reading in the Spirit Megathread that the pots are shoddy and need replacement. I have wired and built my own basses before so replacing them is no sweat, I was just wondering if their is a diagram on the net for a vol/blend/tone, or any other mods in general. As some of you may know, the spirits have EMG select passive buckers on them with a vol/vol/tone like a jazz bass. Does anybody know a good pickup to swap out that would not require any routing as well. I posted on the spirit megathread but it seems to be a little slow. Also too, what kind of pot would you guys use 500k or 250,as well as a cap. I noticed that the bass comes with 500k but they seem really crappy.
Thanks!