I did this mod yesterday. The clips by the headlights were pretty difficult for me to remove.
This is what I learned:
1.) I removed the air snorkel (4 Torx bolts) that leads from the kidney grill area to the intake tube. It takes 2 minutes to remove, and increases the area available to work by 500%.
2.) I think it's easiest to remove the clip closest to the headlight by removing the upper and lower clip nearest the headlight clip, and prying the grill out a bit, and then going after the headlight clip. This creates a little tension on the grill so that when you compress the headlight clip, it unseats due to the tension. YMMV.
3.) I found it helpful to have a flashlight and to use the flashlight to examine the headlight clip. Once I had the other 2 clips removed, I could get in there with a flathead screwdriver (I don't have panel tools) and put some leverage on the clip closest to the headlight. It took considerable force for me to get this particular clip undone. It was literally 10x harder to remove compared to the remaining clips, which are easy.
4.) Once I had both grills out, I had to use a moderate force to install the new grills, to make sure they were seated. It's easy to look behind the grill once it's attached to make sure all the clips are fully seated and properly installed.
5.) I installed an AFE ram air scoop system at the same time as doing this install. If you are thinking of installing air scoops of any brand, it makes sense to do this all at the same time.
Overall I am happy with the mod. Getting both grills replaced and installing the scoops took me about 1.5 hours. I took a few breaks, but really struggled to crack the code on getting that first headlight clip removed.
Jason - Bend, OR
2011.5 E92 - Alpine White DCT ZCP
Dinan: Exhaust, Intake, ECU, UD Pulley, Pedals; AFE: Air Scoops;