Stock carb differences

Trying to buy a new needle jet and there seems to be two different sub-models. BikeBandit lists the differences as "Area A" and "Area AC", with no explanation of the differences.

I don't have the factory service manual yet. Ordered, should be here in a couple of days.

Anyone know how to tell which one I should order?

Thanks

Factory Service Manual came today. Spells it out very clearly in the Fuel section.

The "B" model is the California Spec version and is stamped on the outside of the float bowl.