Another tool to use is a spark plug thread chaser. Most Auto Parts stores carry them. Craftsman Spark Plug Hole Thread Chaser - Tools - Mechanics & Auto Tools - Automotive Specialty Tools
. I think 14mm is your spark plug thread size. Take an air hose and blow all around the spark plug hole to clean the area. Put a little dab of axle grease on the thread chaser to keep metal and dirt out of the cylinder. Use a shop vac to suck anything out of the hole when done.