After looking under the tank to determine how much room there is for a filter, it turns out that everyone's concern of clearence is unfounded. Once the airbox is removed, the amount of room is well over 6 inches. A long straight filter or an offset pod filter will both work fine.
Being the case, I've ordered a two-stage pod filter from Uni, through my local bike shop.
The part number that you'll need, if you follow my directions directly, is UP-4200-ST.
Variants of the
first number changes the LENGTH of the filter. For example, if you wanted a 6" filter, you simply ask for a UP-
6200-ST