TM 9-2320-209-20-3-3 18-12. COMPANION SEAT REMOVAL AND REPLACEMENT (EARLY MODEL TRUCKS). TOOLS: 9/16-inch wrench 1/2-inch deep well socket wrench 1/2-inch box wrench SUPPLIES: None PERSONNEL: One EQUIPMENT CONDITION: Truck parked, engine off, handbrake set. a. Removal. FRAME 1 1. Working in cab of truck, tilt back companion seat cushion (1). GO TO FRAME 2 18-34