I changed the ole plugs today. It went smooth and took about 45 to 60 minutes. It is scary removing plugs that have been in an engine so long (106,000 miles) Denzo SK20R11.
Some tips:
Remove the coil pack connector before removing the coil pack mounting bolt. This way you wiggle the connector off with some force. Depress the tab and use a large screwdriver to wiggle/wedge the connector off. The bolt size is 10 mm. I used a 5/8 inch deep well socket to remove the spark plugs. It is a spark plug socket so it has the rubber bootie inside it to retrieve the plug. The plugs are buried in the block, so a couple of socket extensions are needed.
The head is aluminum so in this case I would use a torque wrench! The torque is 13 ft-lbs or 156 in-lbs.
I had to remove the air filter and filter housing to get to the last two plugs.
I also took opportunity to spray the MAF (mass air flow) sensor with contact cleaner.