RZ 900 s gets a 1000 diff upgrade: Roll pin technique 

Dads 900 s had some front diff issues. it was time to buy a replacement, so was a great time to upgrade to a 1000 diff. I used a oem brand new differntial for a 2014 xp1000, i believe the 2014 xp1000 had the better sprague. was a fairly easy process, for the differential itself all you need is a spacer for the front, and to cut and or drill some holes. you may need to modify your winch mount like i did. will see how this holds up. Hope this video might help you out, see what it takes to do the swap and what to prepare for