The supplied spark plug spanner is indeed one of the easiest ways to get them out, I have done this on mine (-04 too) as the tank is fairly easy to remove I took it off and there was little problem removing the plugs.
The hardest part is not cross threading them when putting them back in, it maybe worth trimming a little of the ends of the plug leads too, and make sure the plug caps really are fitted back tightly, one of mine wasn't and it gave me rough running once I washed the bike!!
Cheers
P