I own a pair of Polaris 570 ATV's. I bought them new in 2014 and I believe that's the model year. Might be 2015 though. On Amazon I purchased the "Kolpin 21561 KXP Rhino Grip Pro ATV (Polaris Lock & Ride Compatible)". I was not expecting this but there's a piece that goes below the big screw and I suspect they want me to take off the big black plastic / metal piece where the holes are and add the locking piece at the bottom. is that correct? Or do I just remove that bottom piece and screw it in? Thanks in advance for the help.