I've not seen a shaker in person on a 71-73, but Ford did explore the option in prototype stage. I have seen the 68-70 turn signal scoop done. Neither one looks right at all on these cars.
Great photo Hemikiller. Guess I'm just so used to seeing the Shaker on a 69-70 Mustang it just looks strange poking through the hood on a 71-73.
And...Just to give you a good ideal of how early the designers and engineers actually start working on the next new model, check out the date placard next to the car on Hemikiller's photo. 3/28/69!!
Gives you a chance to see things your glad didn't make it into production.
Kinda feel like the hood would be too long for a shaker. They look a million dollars on some cars, not so much on others. Just my thoughts. If you like it then go for it.