The PCV system on the Z like many cars is in two stages, the first idle and low load consists of a hose from the drivers side cam cover to the plenum with a non-return valve, and since the VQ motor breathes quite a lot of oil vapor at idle and low load due to high intake vacuum, which results in oil pooling in the lower part of the plenum, this is the one to add a catch can to, but it must be a sealed unit otherwise any air leaks will cause un metered air to be drawn into the engine and weaken the mixture,
The second part is on the passenger side cam cover, which is the high load side and is not subject to high vacuum, and a hose runs from the cam cover to a point on the plastic intake which is often removed when a pop-charger or different intake pipe is fitted, this is only under suction when there is enough velocity in the intake to put t under vacuum, so the pipe can just be reconnected to keep a mild vacuum on the crankcase if you want to utilise this, or run to an open catch can or even just air a filter to avoid minimal oil mist.
Edited to correct my **** up.