I have a stock '72 402 and have been chasing a "hunting" idle and narrowed it down to the PCV valve. I have been using a PCV with a 90-degree, 3/8" barbed connection for a long while. I just went to the auto parts store and the one it calls for is a straight PCV valve with no 90-degree elbow

. I pull the vacuum right off of the front of the base of the Q'jet and it goes into the grommet on the driver's side valve cover. I have a breather hose in the very back of the passenger side valve cover that goes into a small arrestor and up to the air cleaner. The oil filler cap is the snap-in one also on the front of the passenger side valve cover.
Show me your stock setups.
Thanx,
Bud