Removing a side mirror
It most likely has a flat and a tab to keep the lever from rotating in the door.
There are 2 or 3 tabs that are touching the threads
CAREFULLY lift one tab at a time and move it over a thread. Do the same rotating around the threads.
Red are the lock tabs
Yellow are the flat alignment tabs
Green is the alignment tabs for the door skin
There are reman clips available 521 Restoration has them but they might not be the same.