I wrote: > Go to your autoparts store and look in the help section. > There is a sparkplug adapter part. It's 18mm you will > have to tap the inside of it to 12x1.25 and cut the top > part off to get the older type O2 to screw in. Was there the other day they are called Spark Plug Non-Foulers. RK -- Ray Kawski 1998 Sentra SE Turbo, 1991 NX 2000, 349K mile 1991 Sentra SE-R Poconos, PA