Intel i5 760 and stock cooler

Hi, irecently installed this processor and the stock cooler. Idle it runs less than 40C but can get above 75C in the prime95 tests.

I have read some posts about removing a plastic cover from the bottom of the stock cooler, over the thermal pads, before installation, however, i didn't do this and don't remember seeing one present.

Can anyone tell me if indeed this stock cooler comes with plastic cover or not? Certainly the installation instructions don't mention it.

thanks for your help.