Schematic illustration of the revealed merging system. Top: configuration where the near side of the secondary galaxy is on the north side. Bottom: configuration where the near side is on the south side of the major axis. Left panels: discs as projected on the sky. Right panels: a ‘3D view’, with a different viewing angle, for which discs can be represented with no superposition. Top-left panel: highlighting of a potential dust lane in Fig. 5.