1970 Dart Dash

I would think you could swap the metal dash frame from a 69 to a 71 without much trouble. I think the trim(if used) would fit the existing holes, or would at least cover them and require minimal work. You can see from the pic that Adam posted. As for the 70 Dart, the standard guage dash frame will swap (fit) from the 69 to the 70, but the 70 uses far fewer pieces of trim so you might have extra holes to deal with (with the exception of the 70 Dart GT which is the same woodgrain dash as the 71 Dart Swinger).