[chato de shamrock]

This is my first time using photo etch parts on the exterior area of the model and had a question on how I'm support to put on some photo etch bonnet pins. I painted the car and added some carbon fiber decal on the hook of the car. I still haven't clear coated it yet but I was wondering if I had to scratch some of the color, decal and clear coat off so I can glue the photo etch or can it be glued over the clear coat? How do I go about doing this? Thanks guys.