Dashboard frame

I don't think any Dart with the exception of the Dart Sport came with a "Rally" Dash. They all have the short and wide sweep speedometer. If you compare a Dart dash frame to a 69 Barracuda or 1970 Duster dash frame you will see the opening in the metal is larger (longer towards the steering column) for the Barracuda/Duster.

What is your goal with the dash?