999 170 189 9A - Spark Plug NGK BP6ET
NGK BP6ET - 3 ground - GTS - 92 to 95 Special Spark Plug
Original 5.4L GTS cars used a three electrode spark plug. Original part number 999 170 189 90 superseded to 999 170 189 9A.
This is a direct alternative to the more expensive Bosch WR7 DTC.