This may be well known already, so forgive me if I am rehashing old news. I have found that using a spark plug socket with a hex on the end makes the job much easier. The socket I have is a Craftsman 13/16″ with a 7/8″ hex on the end where the 3/8″ socket wrench attaches. For the majority of the plugs I install the socket only, then use a 7/8″ wrench to turn the socket and plug. I have never needed to go through the firewall plug while using this method, and it takes me about 15 minutes to do a complete plug change on a cool motor. Good luck.