How do 360 4 Barrell emblems mount?

How do you manage to get the plastic retainers to stay on the panel while you jam the emblems in? My emblems have held up great for years with the way I did it. I have a few plastic retainers left and I'm missing a "DART" emblem from my car so I can snap some pics of the holes if necessary.

Why would his new emblems come with the retainers already installed??
View attachment 1715104764
Where can I buy/purchase these 'insert plastic retainers'??? Thanks Olenavy72Dart Tampa