They use barrel nuts. I will check the size I ordered and post.

They use barrel nuts.

that is the factory correct option. However clear silicone works too, I use it and I do have a package of the nuts. Nuts chip paint and give a spot to rust (a friend pointed this out to me) and while not a big deal it was a consideration and why I use silicone. cover the post well, use some on the back side of the emblem, put it on, use painters tape to hold in place/setup and good to go. Both options work, up to the individual which they prefer. I will admit and this should be considered... I do find it easier to remove the emblems if nuts are used.