TM 9-2320-209-20-3-4 (2) Second reduction drive chain. FRAME 1 1. Using 1/2-inch wrenches, unscrew and take out screw and washer (1) and nut (2). 2. Using 1/2-inch wrench, unscrew and take out screw and washer (3). 3. Take off cover (4). GO TO FRAME 2 19-88