I can't comment on the 2 piece plugs the 04-10 5.4's have, but on my 97 5.4, the rear passenger side (#4) and the drivers side (#7) was the hardest to get to..
I didn't have to remove the fuel rail and I changed the plugs twice on that rig! (255,000 miles total before I traded it for the new one).
The plug socket I got had a built in universal on it. From there, I had to use several different extensions and other universals to get an angle I could turn the wrench..
I never had the issue of breaking the plugs with mine, but if you have the tool, and break one, that's supposed to be the trick to the whole deal..
Loved the 5.4, but hated those damn plugs!! :)
Mitch
