mileage = 76359mi
Changing the spark plugs was a pretty easy job and it was long overdue. My 1999 Honda Civic EX Coupe was bought used, so I can't say if the plugs were ever replaced, but my guess is that these might have been the original plugs.
Torque wrench with 3/8" drive
5/8" spark plug socket
I decided to buy the NGK G-Power Platinums (ZFR5FGP Stock No. 7098) from AdvanceAutoParts.com for $2.98 each. The final bill was $12.75 and came from PartsAmerica.com.
Following the owner's manual was pretty straight-forward although I had to re-read it to verify that I just needed to pull and wiggle out the ignition coils. Once the ignition coil is removed, the spark plugs can be removed with a socket wrench and extension.
Luckily, I didn't have any trouble removing the plugs, but there was some squeaking while loosening one or two of them. I bought a magnetic tool to take the plugs out, but I didn't need it because I think the socket was magnetized and the plugs came out with the socket pretty easily. My only trouble was the socket and plug being disconnected from the extension. Fortunately, plugging the extension back into the socket worked and I was able to get everything out of the well. All four of the old plugs were pretty nasty and the tips were long gone.
I did use some anti-seize on the threads of the new spark plugs, so I hope that I don't have any trouble the next time I change plugs. The Honda Owner's Manual says to torque the plugs to 13 ft/lbs, so I did it by the book. I believe the NGK site specifies 10.5 to 18 ft/lbs, but 13 seemed to be a little tight to me. If I have trouble, removing these newly installed spark plugs, I might keep them a little looser. Overall, replacing the spark plugs was easy and well worth doing it yourself. I'm hoping to get noticeably better gas mileage.