PS: take it back to the builder
If that was your friend, well, not much to do there. I don't think you have a ring problem w/ no pressure coming out of the breather hose and the dia. of that hose is fine. It should go back to the oil tank from the breather cover... at least that is the path on my NA 3.0l w/ the same CIS system (my assumption is no EFI/Carb conversion).
If you over fill the oil you get oil in the air box and lots of smoke. So if you are not smoking like a dance floor then you are fine. You can always drain some out if you are worried
If you are still in break-in and the rings have not seated your compression test results may be suspect.
Best of luck!
-Michael
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Michael
'82 Euro SC 'Track Rat' 22/29 Hollows, 22/22 Tarrets, Full ERPB F/R, Rennline Tri Brace, Glass bumpers, Pro 2000's, 5 pts, blah blah blah
'13 Cayenne GTS