What is the exact modification, I have to do to the safety 21 roll bar to fit in my 2006 s2000

 

For MY2006+, you'll need to modify the foot for the passenger side main hoop since the floorpan is different than the previous years. Otherwise, you'll only be able to use a few of the bolts securing it.

Here's an install for the 6 point which is basically thesame except you can skip the front hoop parts.
https://www.s2ki.com/s2000/topic/455...hl__cusco+cage

edit:

found a 5 point DIY
https://www.s2ki.com/s2000/index.php...f=148&t=480944

 

Thank you so much for the help