The Broken Fiat Club

That's going to clean up the area nicely.. Is AOS being replaced with a catch can?

Yes. I deleted the AOS a few months ago. I capped the hole on the valve cover. The intake PVC port was capped at the intake using a 9mm silicone cap.
(the PVC valve - the actual plastic removable valve - it a ticking time bomb in my estimation. Not a matter of IF it will fail, but WHEN it will fail.
Stock 18psi was pushing much less the additional psi generated by phase 2).
We extensively dissected & tested (a spare one) the plastic pvc spring check valve before removing it from the car.

I used a 28mm bung plug to cap it while I waited for the valve cover to come back from powdercoaters.
I shaved the lip (on the new one) and then tapped it for an Earl fitting. The vacuum pull is coming from the large port on the ATM for the CC.

The Neon guys deleted their AOS long ago with no problems - It looks like it is nearly the same AOS as the 500 uses.
Before deleting it, we bought one from pull a part & dissected it to fully understand what it did & how it did it.

How were you venting the crank case with the bung capped?

I was venting through the other opening in the valve cover.
My OEM valve cover had hard 2 outlets.
I bought a valve cover from a 2015 for my mod, as it only has 1 hard opening (its other opening was in the removable oil filler stack).

That’s what I figured, just couldn’t see it in the pictures

Some random pics I just found - this was from when I was shaving it all down.