How to convert VPI turntable to banlanced?

The VPI terminal box comes wired correctly from the lemmo plug to the XLR's. Buy the one wired in Nordost Valhalla and the XLR phono cable from them and you won't be disappointed.
It's a bit fiddly to fit, you need a good set of small imperial sized allen keys to do the swop.

I would say that the Valhalla is better than stock but I preferred a JPS Aluminata phono.
Don't know what phono cable VPI uses, but it still sounds good.
I would say that if you are running - or planning - a fully balanced system then you are already aiming for the high end.