Cut the track to take it off, easier IMO. Maker sure you back off the rear axle 20 turns. Go thru your skid, depending on how much aggressive riding you do, the center shock axle ( lower ) had slotted out my skid rails in my F series. Grease it up, verify all movement, make sure nothing is binding. Cats are notorious for boogey wheel failure, rubber cracks and breaks away from the injected wheel. Bearings are always good. Cat dealers that don't stock many parts will stock 50 boogey wheels. Real money maker for cat & the dealer. I have the empty wallet to prove it. I normally pull the diamond drive off open it up and inspect, or the gear box the same. Check for worn chain ect... Seal it up with Threebond liquid gasket 1194 or RTV. Clean surfaces, apply sealant / RTV assemble bolts hand tight, let sealant set-up for 20 minutes approx. then torque to spec. If you do this almost guaranteed not to leak. Don't forget to tighten up your oil drain plug, that way when you refill it , it won't run down the threads and appear like a bad sealant job and have you tear the cover back off. I don't know if you have the diamond drive or not but you can pull the unit and not drain the oil if you choose. Watch for your sensor wire ( reverse ) rubbing. I normally will go thru everything I can looking for stuff like rubbing wires. Dumb $%#@ wire will touch/rub the chassis and sent you a CCU code. My .02 ! Oh 1 more thing , if you plan to stud it get the track on and then install the studs.