Hissing near brake pedal?
 

Hissing near pedal when not pressing the brake
im assuming this would be the brake booster? If so how do i get the fuse box out of the way to replace the brake booster?

Check the plastic fitting for the vacuum line to the booster, that is the weak link.

i already did, no bueno, im thinking it's a diaphragm leak from the booster itself

Welcome to the site, here’s a detailed how to

https://www.chevyhhr.net/forums/www....ad.php?t=59520

Here's a video to help.
Once the top part is off I would guess pretty straight forward to remove the bottom part.
I myself have not done this.

Another video to replace master cylinder

He's not replacing the booster, but there should be enough information there. Guy talks too much, and he is not great with the camera. But it should do.

At least he gets the master cylinder outta the way