Same as Fig. 3, but for (a) IRAS 15194-5115, (b) IRAS 15082-4808, and (c) IRAS 07454-7112. The figures show χ² values for our grid of CS models for the above sources. The contours denote 1σ, 2σ, and 3σ ranges, when constrained using only the spatial information from the CS J = 2 - 1 line (green) vs just the excitation information from the different J lines (blue). Also shown are the contours when using both the spatial and excitation information simultaneously (red) to constrain the RT models. The green, blue and red stars mark the best-fit models as estimated from the above three cases, respectively.