To make the installation task easier, lay out the snow plow mounting plate components before you begin. There should be a main mounting plate (the large piece), four smaller rectangular spacer plates and two side plates. There will also be assorted 5/16-inch hex bolts, Nylock nuts, flat washers and hex bolts. Organize these parts.
Bolt the two side plates to the main mounting plate with six 5/16-inch by 1-inch hex bolts. The bolts should be threaded through each side plate (left and right sides), and then through the holes in the main mounting plate. Secure each bolt with a flat washer, followed by a 5/16-inch Nylock nut. Tighten them securely using a socket and crescent wrench, twisting clockwise until tight.
Remove the radiator shroud from the Polaris by pulling out the three plastic push-pin type retainers that secure the radiator shroud in place. Remove the shroud and set it aside.
Use six 5/15-inch by 1 ¼-inch hex bolts to attach the two side plates to the radiator bumper tabs. Before inserting the three bolts on each side, carefully slide a spacer plate between the radiator bumper tabs and the side plates. Without the spacers installed, the mounting plate will not side square and level. Carefully align, and then tighten all six bolts using flat washers followed by 5/16-inch Nylock nuts. Tighten the nuts with a socket and crescent wrench, twisting clockwise until tight.
Attach the winch to the mounting plate using the winch manufacturer's hardware. Attach the snow plow to the Polaris frame and mounting plate using the snow plow manufacturer's hardware.