My eyebrows used threaded studs and nuts with built in flange washers. The eyebrow goes up against the fender on the outside, then the headlight bucket goes up against the fender on the inside. The stud has to thread into the eyebrow, pass through the fender and headlight bucket, then the nut goes on. There are 3 of these studs that hold each eyebrow on. As mentioned, it is a very tight area, hard to get to even with the fender off the car. Attached is the best image that I have that shows the 3 round holes for the studs. My headlight buckets were beaten up a little and I had to repair some of the holes where the studs went through as seen in the photo.