What is the proper way to rotate a Motor6D?

I am trying to get the arms to point in the direction the the camera is looking.. This is what I have so far but when looking strait up the arms wont aim strait up. Im not sure how to fix this.. Any ideas?

This is what I have:

Chr.Torso["Right Shoulder"].C0 = CFrame.new(1.5,.7,0) * CFrame.Angles(((Camera.CFrame.lookVector).unit.y),0,0)

Chr.Torso["Left Shoulder"].C0 = CFrame.new(-1.5,.6,0) * CFrame.Angles(((Camera.CFrame.lookVector).unit.y),0,0)

Chr.Torso["Neck"].C0 = CFrame.new(0,1,0) * CFrame.Angles(((Camera.CFrame.lookVector).unit.y/3),0,0)