Brake line adaptor, 67 Dart Gt, original KH disc

Ok OEM gurus...

67 Dart GT, 273 2bbl, original KH front disc.

My Dart has brass adapters on the MC. I always thought they were add due to a replaced MC that was not correct. ( Have no evidence of this but my dad was know for adapting things some times)

A local old timer said they were OEM with disc brakes.

I can not say I have ever seen any on other cars.

What say you?

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