They are called barrel nuts or clips. Melvin's Classic Ford parts has them. https://www.parts123.com/
OK, so I got the barrel nuts, so now how do you get them to stay on? They slip on and then slip off. What is the trick?
They pop into the hole in the fender (or other sheet metal) first and then the script emblem presses into the holes. They do come in several sizes - you have to make sure you have the right ones for your pin size. The fit is quite tight if it is all right. If it is loose, something is wrong.
Thanks Acorn. Never thought of that, I know I pulled them off the back when I took off the emblem. Thanks