rksport doesn't offer headers for a 1993 Z28, heres the link for the ones i have....
http://www.rksport.com/product/p_01096556/view_detail to be honest i don;t know what the difference in the 93 and 94-95 application is, it might have something to do with the emissions hookups, which you can always get around, or there might be clearance differences, heres thier number, you can call and ask them what the difference is. 951.894.7883