all u need to do is acquire the RA40 diff, bolt it all on, get ur stock panhard rod mofidied, or get an aftermarket adjustable one (whiteline) and see if the wheels your running will fit inside the stock ae86 rear guards, if not, pump em
you will need a JDM/T18 tailshaft as the stock ae86 one won't bolt up right.
as for the LSD, anything that will fit a Zenki T series will work - do a search on the for sale forums for group buys