Factory 1994-1995 Magnum 5.9V8 engines had a Air Breather on the driver’s side and the PCV on the passenger side.

This factory Air Breather had a hose nipple, which connected to a hose that connected to a nipple at the air cleaner housing.
You could just leave the nipple unconnected.

The factory PCV valve does not have a good design of baffles beneath it and lets a lot of liquid oil droplets get through to the intake manifold.

A catch can to trap this oil is a good addition.

The oil that gets by could cause idle stumbles, as the oil is equivalent to extra fuel.

It can also cause pinging/pre-ignition due to carbon deposit build up on “soapdish” Magnum piston tops.

Yamaha “Ringfree” is a good carbon deposit remover
as is BMW dealership “Ventril Sauber” by Lubro Moly GMBH.

If the Megasquirt can be adjusted to run good on a Magnum style V8 I would like to try that in order to run a very lean air fuel ratio and a wide range oxygen sensor.

Best of luck.