Where are the Seatbelt Mounting Points in 68 BArracuda Fast Back

My 68 fastback, was built in late 67 and has front and rear lap belts but no front shoulder belt.
When I purchased this car it was original. No modifications.
It is my understanding that cars built Jan 1 1968 and after, front shoulder belts were mandatory.

I will feel around the headliner to see if I can feel a shoulder harness mount.