That tool looks a bit thin. I've used a Rowe wrench to good effect...and then you don't need to know what size you got.
The 'thing' at the other end of the spark plug wrench in the kdx toolkit is a waste of time. You will only end up messing up your nipples.
Don't want that! goin' on!!
In any case, unless you have taken all your spokes/nips apart and put some anti-seize agent on 'em you aren't likely to use any kind of wrench to get anything adjusted.
Well...maybe with an '04 there's a bit of hope. Unless you've ridden it already. ;)
Good luck!
M'cycle USA has that wrench for $4. Of course, shipping is probably twice that. Any decent bike shop should have a Rowe wrench.