I can't speak for the Polaris 2.6 / 163, but I can tell you that the 3" x 162 powerclaw is the best track I've ridden, and i have (or had) an X3, and a cut down 16 wide Challenger extreme (the same pattern as the new 3.2). To install the 3.0 pitch track on your sled, you need a set of Avid drivers in 3.0 pitch, trim 1.5" off the front of the rails and install an anti-stab kit, and likely make some clutching changes. I installed a PC 2.6 on my wife's 660 Pro RMK with 8 tooth Avids, and while it is a tight fit, it does fit - would likely go with 7 tooth Avids if I was to do it again for extra bulkhead clearance. BTW, the 2.6 PC was a huge upgrade over both the stock 2.4 and the Challenger Extreme 2.5 that were on the sled previously - pretty sure any sled I own in the future will have a powerclaw installed on it from now on.
