The June 2001 issue of 5.0 Mustang magazine used NGK UR55 plugs. They say that they are basically foul-resistant due to a split in the electrode.
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Blueneonman - '95 5.0L Mustang GT Convertible | K&N Custom Cold Air Intake | FMS 9mm Wires | Hollow Cats | Flowmaster 2 Chambers | BBK Subframes | 6-pt Rollcage | 14deg Timing | King Cobra Clutch | FMS Adjustable Clutch Cable | Coolest Neon Lighting on a Mustang EVER!
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