doing your own supercharger sounds cool, but is a pain in the ass!
as you have to get the right % belts for alternators etc, its alot more work then it sounds
vince g60's are not hard to get, i got offered loads, one with alot of work done (reciepts to prove) was worth like £700 but as i know him wanted £500, but i cannot afford it, he sold it in the end for £700 straight away!
but no point doing it like what's been said, it's cool and will sound great, but do you wanna get stupid MPG and cost like £2-3k?