I've read a number of post on this site regarding the difficulty of getting the two part, spark plug out of the block. In addition to following this site I've done a fair amount of research on the 2008 Mustang GT/CS convertible and came across an article about the plug and how to tell if your car has them. Today I had the car serviced and talked with my mechanic about the two part plug. He suggested if the car had the two part plug he recommended a tune up and pug replacement between 60 and 70,000 miles. If the car had the one piece plug he was OK, with the 100,000 mile as outlined in the manual. Him citing the difficulty with the plugs separation. Again, referring to the article on the plugs it stated if the car was manufactured pre November 2007 it will have a black coil boot and two piece spark plug. If the car was manufactured after that date it will have the revised 12mm one piece plug with a brown coil boot. When they pulled the plug I was pleased to see the brown boot.