[bradlington]

I hope the old style of drawing line diagram represents what mu intentions are .

Once I have this I can remove the whole airbox and only use the Cargo large Cone direct onto throttle body.Previous placement of the cone filter directly on throttle body resulted in some additional noise when sudden acceleration - sucking sound - but plan to place a metal shield over it to make use of majority of air to be pulled in from hot engine .

The "failover protection " PCV connection , which has lower vacuum than the main PCV (a proportional relationship to main pcv flow) can then be used for whatever combination I want to inject be it HHO-water Fuel vapor , mist or perhaps all of the mentioned .
Once my new exhaust is on next week and the wideband AFR meter installed I would be able then have a good way of accounting for various changes being made .

One up on the Subaru design - I see many other makes of vehicles do not have this PCV failover design .