My friend, the way I went about getting plugs for my 98 4.0L SOCH was to go to auto parts stores' web sites and getting info. I ended up going to AutoZone and buying 6 plugs...they are MotorCraft double platinums...only use these plugs or you will have problems. They are about $6 a piece, and I hear they are the same cost at the dealer. For wires, I bought them at PepBoys for about $40, which is way less than the dealer charges for wires, and they work great. As far as exact stock number for plugs, I can't help you. But AutoZone should be able to pull up the right plug...they are the only ones I know of that carry MotorCraft plugs. I hope this helps.