You wont have to change anything. I ran RZR2s w/ ITP rims. Just because it is a 10" and not 11" doesn't mean you have to change around your gearing, that is just the diameter of the wheel. If you get the same size tire (out side diameter) like 22", then it will be the same, if that makes sense. A lot of people change to a 13t front for better low down gearing for woods riding and what not.
2008 700xx; Power Bomb header with power core 4 exhaust, Power Programmer III, pro armor nerfs, prm products control front and rear bumpers and full skid, 10" ITP rears, ITP Baja's fronts, RZR 2's all the way around, Uni filter, 13t sprocket, CCP steering Damper, DS450 shock swap, Dual Gasser Throttle, bar risers and Moose barkBusters. 730XX kit plus other engine mods!