If you have been tracking the C5 issues, one is the LS1 eating oil.
Some have to put a quart in for every 1,000 miles or less.

One of the claimed issues is the PVCs lay horizontal and when PVC is open,
it causes oil to back up into the intake manifold and burn that oil causing
lots of carbon buildup in engine causing more knock.

So the claim is if the PVCs were vertical the problem would go bye bye.

Here is the next Rebel project I just finished.
http://teamzr1.com/pvcinstall.html

It has images of my install process.

In short inline to the PVC that gets tied to intake is now two filters and horizontal is
a drain tank so that oil no longer can get into the intake.

See if you buy the thought process and you think it's going to work ?

I'll begin testing to find the real answers . . .