I just removed the plugs (motorcraft awsf 32p) and was in the process of replacing them with autolite ap104 plugs. I noticed the motorcraft plugs have threads half way up (like 3/8" worth of threads) and the autolites have threads all the way up to where the plug seats (a little over 5/8" worth of threads). Is this a problem? I checked with three auto supply places and they all said the ap104 is the right plug. My worry is the plug threads down into the cylinder farther and hits the top of the pistion? Any advice? Thanks, Ron

 

They will work fine, it is an updated thing because in 03 they added threads to the heads. They will work fine. If you measure the seat to the bottom of the plug, they will measure the same.