I changed my sparkplugs in one hour and fifteen minutes from the time I opened my garage door. Armed with a 3/8" drive ratchet, assorted 3/8" extensions, a 3/8" breaker bar, plug socket, floor jack and jack stand. I have a '93 EXT with the 4.0L.
I was able to change the 3 driver's side plugs from under the hood. The back one was easy with the socket and breaker bar. The bar doesn't have the large head of the ratchet and works well in the small space.
The two forward passenger side plugs were done from the wheel well. I did not remove the tire, I just jacked and supported from the frame so the wheel clearance was increased.
The infamous rear plug was easily done using the breaker bar again but from under the car.
I checked the gap of each new plug before I installed it. All were below the minimum spec gap. I never had to remove the engine cover but if you plan to replace your wires you will need to. The Bosch plats a replaced with 30K miles were in pretty good shape but the no. one plug had a heavy accumulation of light brown deposits on the tip and electrode. I don't feel any change in performance but I am hoping that my pinging goes away when the weather warms up with the new AutoLite double plats.

 

Vango:

Heck, I'd say that's a world record

No matter what I do, it still takes a whole day, if I don't screw up.

 

I did mine in 45 minutes, including tool cleanup. The first time took three hours though. I wouldn't have had a second time if I had just used the Motorcraft in the first place.

 

Oh yeah, well I took a lunch break while changing mine

I might get it down to 1 hour, but 45 min would give me a hernia or something! I wouldn't let a shop charge me more than 1 -1.5 hours for the job though.

 

you guys work too fast.

but I guess that leaves you time to do the dishes and laundry after the wife sees you loutering in the garage

i can make changing oil an all day job. get the rig up on the ramps. throw down a soft deep pile carpet section...slide the case of cool ones underneath in the shade. slide under and make the day of it...been known to even take my little 5" battery TV under to watch fishing shows or football
no snoring allowed. DEAD giveaway

 

Snoring? No Honey honest, That was me Grunting. Theres a bolt under here that doesn't want to come loose.

JaY

 

That is pretty good time. I always break down and remove the engine cover to do mine. Usually do a LOF while I am under changing that plug.