I have the haynes and it seems great. The only change i know of besides paint is in 05 they made the headlights go out when thumbing the starter.
I believe they did that in '04, along with adding 4-way hazard lights that earlier bikes don't have, besides those minor electrical changes, no difference from an '03.
OH! One other difference - '04-'05's have a one-piece midpipe/muffler where earlier ones had mufflers bolted to the midpipe - and California models got cataclysmic converters in '04.