273 copper head gaskets SCE

We did a clone 66 D Dart 273 and did the max weight reduction. In a Burgundy 1965 Dart GT everyone thought it was a 340. A racer Brown cam, 780 CFM Holley, fenderwell headers and a 4 speed.
Any pictures of that '66 dart. There's a YouTube video of a white one with red interior. They took it for a spin up and down the street and that one had a 340 in it. Sounded pretty nasty