my setup is closest to # 6. the big difference is i kept the oem boxes. gutted everything and used k&n's.
rob does a great job with the devil horns, and if you have access to some tubing the tubes can be made very cheap. i have less than 300$ in mine now complete with the sl55 y splitter and tubes
i was able to keep my centerpiece and still get great airflow.
i guess great minds think alike!!