Apply some petroleum jelly to the surface of the spark plug you are going to drill and tap out. The PJ will catch the small shavings and keep them from falling into the cylinder when you back the plug out. Drill the hole slow and it will keep the chips bigger and easier to clean out. Also make sure that you don't drill completely throught the plug as it will blow out the back end and all that stuff falls into the cylinder and is near impossible to get out unless you crack open the head to get in there. EZ outs are great but be carefull you don't go frying pan to the fire.