they will fit in to b16a ,
The manifold are one piece type , from the top header mount to the catalys adapter ,
if this o2 sensor wont fit to your plug , you could use your stock o2 sensor .
Would anyone know from which car accessory shop i can buy/order a Vspec Emblem for my R34 ? needless to say, the closer to Malaysia, the better. ;)
thanks.