On the 70 Challenger's there's a bracket that bolts to the front bumper, then that bracket holds the license plate. Maybe the Cuda's are the same or similar? Sorry, I don't have a photo to show you.
Gotcha now, didn't realize you already had the bracket for the plate. And to tell the truth, I've got two of the brackets for my 70 Challenger but I've never had them on the car. Don't remember if there is mounting hardware with them, or what it looks like???