I've decided to do some minor mods to the intake so I bought the red tube & BMC filter. I was about to give up trying to remove the airbox to install the filter till I found this old thread. Thank you OP!!!!

DIY-Replace\Change Air Filter Remove AirBox

For 997 "S" only
Additional tips

Op mentioned "push metal clip in Then pull wire harness out".
It's more like push wire clip in & pull upward

To remove the vacuum tube, it's easier if you peel back the tip of the rubber with your finger all the way around. You will hear a hissing sound. That will release the suction & the tube will slide right out when you pull it. If you try pulling out without releasing the suction, you may snap the tube.

hope this help someone. took me over an hr figuring how to remove the darn thing without breaking something.

 

For mine I pulled off the vacuum hose from the solonoid and left it attached to the airbox.