What might be confusing is that there are several different lug nuts with the same thread (M14x1.5), and what you have to search for (for Mustang OEM wheels) is an "Acorn bulge" type.
The Gorilla part #61148BCX for the regular nuts and #96641BDX for the secure nuts.
The regular ones seem to have some kind of dry film dirt on them, but once cleaned up they look pretty good: