I always thought the Seibon was a slightly different profile and shape, never looked that closely. However, is it basically just a direct copy (appearance wise) of the 02+ OEM valance?
Seibon:
2002+ OEM:
Sorry if this is obvious and I'm missing something...
Seibon:

2002+ OEM:
![jp02-18[1].jpg](/proxy.php?image=http%3A%2F%2Fwww.scienceofspeed.com%2Fproducts%2Fexterior_performance_products%2FNSX%2FHonda%2F2002%2Frear_valence%2Fjp02-18%5B1%5D.jpg&hash=0fb7b03b95213151240037683e5ced3d)
Sorry if this is obvious and I'm missing something...