Hey guys, there is another way more thorough DIY for this that applies to e90s and to some extent e92's right here:
http://www.e90post.com/forums/showthread.php?t=3830
I wanted to do one for e92's also because I had a bit of trouble removing my grille using the above method. I wasn't going to do a DIY but if anyone has trouble this may make it a bit easier. Instead of just pulling the old grille out I needed to get behind it and unclip the grille.
Edit: I got this grille from Steve @ Trendix, a forum sponsor.
Here is what I did:
Remove these for hex nuts, 5/32's.
[IMG]http://****************/fp/335i/kevin/grille/grille5.jpg[/IMG]
[IMG]http://****************/fp/335i/kevin/grille/grille1.jpg[/IMG]
Pull the bumper cover back and reach behind the grille:
[IMG]http://****************/fp/335i/kevin/grille/grille3.jpg[/IMG]
On the e92 there are 6 mounting points:
[IMG]http://****************/fp/335i/kevin/grille/grille2.jpg[/IMG]
You need to hold the clip down and lightly pull on the section near where you are unclipping. Now, this is important; by far the most difficult clip for me was the one on the outside of the grille (closest to the headlight); do this one first. Unclip and lightly pull, then move along in a circle and keep unclipping and pulling. The grille will pop right out and will remain re-usable.
Now it's easy, just pop the replacement back in ALL clips at the same time (if you do one at a time the last one is a bitch:
[IMG]http://****************/fp/335i/kevin/grille/grille4.jpg[/IMG]
Repeat:
[IMG]http://****************/fp/335i/kevin/grille/grille7.jpg[/IMG]
Put back 5/32's hex nuts and profit.
[IMG]http://****************/fp/335i/kevin/grille/grille6.jpg[/IMG]
(ignore that might angels and fogs are a different color, I was experimenting.
)