In all honesty you don't need to raise warrior to take out chloris. It is a great job for it as I did most of mine and my friends Chloris's on my warrior dual-boxed with my whm character.
On the other hand, I also dual boxed it as my thf and also my monk with little trouble. I have about average gear (above pink and perle sets though) and nothing else special really. You just have to be quick on the debuffs.
With regard to the GA, you can easily compensate for the drop in acc with food and to be honest, that much -accuracy shouldn't be a massive problem at 99 anyway against chloris. I just used a standard AH Great Axe at the time if I remember correctly. Your Atma choices seem decent also, I used the same atmas when duoing it as warrior. As monk I switched to GH, RR, Apoc.
My one tip which you will already know is take plenty of holy waters to spam (create a macro), you will need them if dual boxing and don't have a backup tank to take over when the doom timer kicks in and you hit the dirt lol.
Other than that its pretty much just engage and whack away lol. The hardest part of the whole thing for me was gathering the KIs to pop him lol.
Good luck with your kills.
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