Any Major Front Seat Floor Pan Differences - '67-69 Dart vs. '70-'74 Duster

ocdart said
I want to have some custom seat bracket/mounts built for my '69 Dart that will be finally coming home from body shop/paint prison in a week or two. Now that the body and paint will be new and perfect, I'm not thrilled about possibly having to take it out to a shop for measurements and fabrication of the new bracket/mounts for the bucket seats.
It was originally a bench seat car and I'm switching over to aftermarket buckets.
One of the fabricators I've talked to has a Duster project at home and he's had Dusters in his shop. Are there significant differences in the front seat area between the '67-'69 Dart floor and the '70-'74 Duster floor? I'm wondering if he could use his at-home Duster for dimensions to build the bracket/mounts for my Dart if I supply him with my aftermarket seats and sliders.
What say the experts?
Thanks.

He can use the Duster for the seat bracket fabrication. The floor pan is identical to that of the Darts forward of the rear seat foot wells. The only difference in the floor pans ‘67-‘74 is the length, and the extra 3” the Darts have in the floor pan compared to the Duster is well behind the front seats.

‘75 had the catalytic converter bump added to the floor, which does change one of the floor brackets. So as long as he stays ‘70-74 it should be fine.