Full service for s13 & 14's is totally worthwhile if you ask me. I know a member here that sent his away and it ran right from start up. I know several DIY'ers who's cars still aren't running right... 6 mos later! <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/sad.gif" border="0" valign="absmiddle" alt='

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As for the s15 - that is a very complicated swap. I also recall the speedo issue. I think there is a problem w/ the abs circuit changing the diff signal. That one is NOT easy and not for the feint of heart.