I tried tonight removing my brother's 2000 Civic EX's intake resonator tonight.

Okay the intake is basically a few pieces. First of all there is the tubing that comes from the top of the engine where the intake starts. This comes down into a 2-piece air box. The black plastic box on the right has the air filter, and a box underneath the filter, the black plastic box on the left doesnt, and underneath both there is the U-shaped tubing.

Which can you safely remove from the stock intake?

THANKS!