If I'm understanding this you would have to either build a mouth piece like mentioned above or get something like an afe blade runner and close off the additional holes for the PVC crap. You can not use the factory mouthpiece because it will leak once under pressure.
My charger came from Mark with a flange on the bottom of the turbine housing so that it pulls from both sides. 600 sounds about right for the gate and misc pipe fittings doing it yourself.