Firstly welcome!
Have a read of this thread for the poly bush guide...
http://www.nissansilvia.co.uk/vbb/showthread.php?t=1869
Most things can be found in the How To section without to much in the way of brain ache. There's plenty of information on what turbos do what best with what mods and so on in there. Horses for courses really. Apart from more power what's your plan for the car? Is it your daily driver?