Pass seat must be installed and equal to or better
than OEM. You can install an aftermarket seat in the driver's side and leave the OEM in the pass, or a race seat in the pass side as well.
Assuming you mean BMWCCA rules.<img src=http://members.roadfly.org/txse46m3/haha.gif height=98 width=152><img src=http://members.roadfly.org/txse46m3/avatar.jpg height=76 width=102>
Disclaimer: I refuse to respond to racist, anti-religious, or other incredibly ignorant remarks made by people in an attempt to break up the boredom of their work day unless those comments are attended by naked pictures of their girlfriend.