The carrier bearing is in the middle of the RZR , just about directly under the shifter. If it's the front diff sprague, it will require a full tear down on it in order to repair. You can also search for Gilbert Designs, they make a replacement front diff & plate so that a RZR 1000 front diff...
Check the carrier bearing on the driveline for the front diff, they are a known problem. They are also known for the front diff sprag issue. Hope this helps
Jumpman23