found this while searching for the 6spd crossmember ala-carte:
http://www.nismo.co.jp/en/products/c...ilvia_spec.pdf
it contains all the part numbers for essentially anything 6spd related on the 180sx/silvia.
ALSO, be advised the throwout bearing is NOT the same between 5spd and 6spd. i don't recall off the top of my head but one is of smaller diameter compared to the other.