Installing Wall Against Ceiling Beam

I am building a 2x6 steel stud double wall with 2 layers of 5/8 drywall on each side. The outer face of the wall will be flush against this hollow soffet? beam? (I'm not sure what it's called) on the ceiling. By doing this I am also going to run into the hearth area that surrounds the fireplace as it sticks out further then the ceiling beam, so I am a little confused about how to avoid that. Does anything seem wrong with putting this wall in that location? Does anyone have any suggestions? I have searched the forum and could not find this kind of situation. Here are some pics http://www.4shared.com/file/103598579/5a49996b/god.html http://www.4shared.com/file/103598801/1 ... /god2.html Thanks

Hai Mordent, Could you please update your profile? Were you @? Read the STICKIE threads also. Please upload your pictures to this forum instead, keep them 640x640 pixels max. That way it's easy to comment on. I'll read into your question later, it's a kinda confusing post (ah, language barrier indeed) Here are your pix (I've uploaded them for you already)