I don't belive the seats or door panels are interchangable.
However with some modification you may be able to use the rear seat if its roughly the same size. Of course I've never seen an s15 in real life, so what do I know. <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/smile.gif" border="0" valign="absmiddle" alt='

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