1967 GT 350 (Early 10/66) Seat Belt Anchor Bolts

[1967 eight barrel]

The Shelby front bolts are the longer shoulder variant, and not the standard production Mustang bolt.  The Y shoulder harnesses are retained by them as well as a chrome spacer. It doesn't use the rubber washers either.

[Andrew@MagMustangs]

And to clarify for others watching later: The bolts you are referring to for attaching the Shelby Y-Belts to the floors are Not the bolts that would attach the shoulder harnesses to the ROOF on a regular production Mustang. They are the bolts that would attach the buckle seat belts to the FLOOR on a regular production Mustang specifically with Shoulder Harness option, and only used on Trans Tunnel side in normal Mustang.