Zexel R32 Exhaust Pipe Question

Hey guys...well, I finally opened up my zexel tamiya r32 skyline. I love it. It will be a street car stripped for the track. I have a question or two tho. What are those lil things that kinda fit over the body panel right behind the door on the rear 3/4 panel, and do they need to be there? Is there an extra exhaust (two straight flow pipes) that can be used to exit on the side? I'm stuck on which of the pipe works to use. Any opinions are very valiable. Thanks.

The skirts are actually Nismo pieces. If you want Nismo body equipment than put them on, if not than don't. I prefer always to put them on as I love Nismo.

The side shot downpipe is strictly race. The full exhaust is of course for street use.

thanks niska.