Take a look at these C2Cfabrication floor pans...

Dana67Dart said
What part of the floor is that supposed to be?
Here is an AMD full floor pan.
View attachment 1715431562

Are you sure they sent you the correct part?

I'm sure. Here's the ebay listing. I need my a** kicked for not looking at those pictures more closely.
1967 1968 1969 1970 1971 1972-76 Dart Duster Valiant Scamp Rear Floor Pans Pair | eBay