Here's an illustration on the parts and how to.
http://www.pilgrimpowersports.com/OEMpartfinder.htm?mfg=Kawasaki#/Kawasaki/KAF620R9F_Mule_4010_Trans4x4/HEADLIGHT(S)/KAF620R9F/I15I1554F2710
A buddy of mine did that upgrade with his Rhino. He bought the said UTV tire size and stuff online and install It by him self. So far he had no problem at all just a small bit of rubbing w/c can be notice in every full turn of the wheel. Handling he said improved and looked really great.