The engine covers are there to reduce engine noise and took look pretty around the edges.

I am in and out of my engine a lot lately so I just haven't stuck them back on. i dropped a screw bit down in my fan shroud a few weeks ago and had them all off. i also don't have enough of those tabs to hold them in steady any more so i just hung the pieces on my garage wall for decoration.

 

I had the same problem when I removed my engine covers. About four of the clips broke. What I found worked real well as a replacement were the clips found on a new Toyota Camry. The clips I used are the ones Toyota uses to hold the trunk lid trim pad in place. They fit great are easy pop in and pop out and seem to be more durable then the Lexus clips. But best of all they are a lot cheaper then the 5 bucks Lexus wants for their clips. You can get them at any Toyota parts dept. Sorry I don't have any pictures to share, camera on the fritz.