TM 9-2320-209-20-3-1 4-23. MANIFOLD HEATER (TOP-MOUNTED, COVERED) SPARK PLUG REMOVAL AND REPLACEMENT. TOOLS : 3/4-inch wrench 7/8-inch wrench SUPPLIES: None PERSONNEL: One EQUIPMENT CONDITION: a. Preliminary Procedure. Truck parked, engine off, handbrake set. Open hood and right side Panel. Refer to TM 9-2320-209-10. b. Removal. 1. Using 3/4-inch wrench, unscrew and take off electrical cable connector (1) from spark plug (2) . 2. Using 7/8-inch, unscrew and take off spark plug (2) . Take off gasket (3) . END OF TASK TA 083337