Where are the Seatbelt Mounting Points in 68 BArracuda Fast Back

Going back to my 68 Roadrunner, I'm pretty sure it did not have shoulder belts, but my memory is not great.

Moving ahead to now, is it possible the mounting holes are there on my 1967 notchback? I couldn't feel any, but it is hard to tell through the headliner. The options chart I have for 1967 Plymouths, says shoulder belts are "special equipment, factory installed."