When your going to do something like this to your car, its best to do the homework first.
The following sites are full of useful information, forums full of helpful people, and proved very useful to me, not just in doing this but when deciding the next crazy thing to do to it next too.
Western Autralian nissan silvia club. Forum for members only, but the club if full of great, knowledgable people to leech off of! Thanks guys!
Online car magazine, many many useful articles, for performance on the cheap. Their "supercharger steal" article was useful.
Google it! Google has to be the most useful site on the internet.