Upper row: PDFs of the orientation of the vectors shown in Fig. 4 with respect to the horizontal axis of the image (i.e., the ξ direction). For every projection angle, we show the total distribution of angles between all successive velocity slices (solid thick lines), the distribution of angles for the blue-shifted components (dotted lines), and the distribution of angles for the red-shifted components (dashed lines). Lower panels: PDFs of the relative orientation between the vectors shown in Fig. 4 and the polarization vectors shown in Fig 2. The shaded region shows a KDE estimate for each distribution and the dashed-dotted line shows a simultaneous fit of a Gaussian and a uniform distribution to the data.