Whats the story on this style seat belt buckles/tongues?

[AR67GTX]

My 66 arrived with these belts that I assumed were originals. The twin square holes in the tongue seem to be an oddity. When Bill Edward’s restored mine they arrived back with what seems to be the more typical twin notches in the sides of the tongue.

These are the style that Bill returned for my 66. The belts in my 67 restored by SnakeOyle are the same.

I noticed this 66 Hemi going through BaT has the same ones my car had. But when I search around about all I find represented for 66/67 are those with the side notches.

Were there 2 styles back then? If not which one is correct? Just trying to satisfy my curiosity.

 

[Don67Satellite]

Mine.

 

[Jerry Hall]

What is the build date on your car, I have to assume it's very early. I have saw those on a few 66's.

 

[Jerry Hall]

The last picture in your post is is a belt with a date code in the 4 quarter of 1965 which would could have made there way into some early 66's.

 

[AR67GTX]

Jerry, That’s from the 66 Hemi that’s for auction on BaT. Says it was built on April 26, 1966. But maybe they aren’t original to the car. My 66 car is from the same time frame. They may not have been original to it either. But sounds like that may be a 65 style buckle/tongue.