You need a 3-phase rectifier are three small rectifiers.
All the windings need to have the ground floated so you have two leads coming off each winding.
Each winding on the stator needs a separate rectifier if you can't find a full wave three phase rectifier.
then run it through your capacitor condenser then to your voltage regulator then connected to your battery if you're using one, if not just connected to your lights and all the other crap you can now use the frame as part of the ground circuit now that you have everything floated from the stator
I like using large condenser/ capacitor it has to have a very small resistor across its connections so it does not discharge blowing your bulbs and are killing you when it just charges in a Flash, I like using very large capacitors I usually find them enlarged sodium or metal halide lamps they will usually have the resistor soldered to them so all you have to do is connect to the blade connectors at the top for voltage Spike suppression.
The large capacitor should be connected to the leads coming off of the rectifiers before the regulator all you need to do is tie them in the current does not run to it just need to have the ground connected to one side and the hot to the other then connect the same way to the voltage regulator and everything should be good with all voltage floated.(edited)