I wanted to pass along a few things I discovered while changing the plugs in my 5.7 VVT Rubicon Unlimited. What should have been a 2-3 hour job went way over. It started with my choice of spark plug tools. The Mac with dual universal joints slipped right in the first plug hole. When I went to remove the plug it wedged into the plug tube. The top was barely sticking out of the top of the head. A few hours later of gentle persuation and finally a little force after getting some images online of what I was up against and it was out. You can see where the rivet on both sides was digging in. Be careful what tool you choose.