[mlambrecht82]

The plugs on your mustang are under the coils right next to your fuel injectors. You will need a 7 mm socket (if I remember right) to pull the coils off the plugs, and then a 5/8 " spark plug socket with an extension, a universal joint might help, but I have pulled my plugs out several times, without them. Just take your time when finding a place to slide the socket through. I've changed my plugs in under 30 mins several times, IMO the newer modulars are a lot easier to change than the older ones, the plugs are on top instead of on the side my the header. The antiseize is a good idea too. You should have platinum plugs which are rated for 100,000 miles. I would change it before 80,000 though, just to be safe. Make sure you gap all the plugs evenly and to the right size, there is no such thing as pre-gapped plugs. Use a wire feeler gauge and make sure that the electrode is spaced at a 90 degree angle, otherweise you will shorten the life of the plugs.