The rough idle can also be something totally different than what the lean mixture problem is. Do you have certain cylinders that are misfiring? A lean mixture from any of the issues mentioned, should effect all cylinders the same, not just one or two.
The PCV is a real pain to replace, and usually all those tubes get broken in the process. A slack-tube manometer can tell you if it's malfunctioning. We use a special tool that fits in place of the oil cap and reads inches of water.
Make sure the oil cap is seated good, as well as the oil dipstick. You can try spraying brake cleaner/carb cleaner around the pcv while it's running and see if it sucks it in and changes the idle.
If you notice a low honking noise if you quickly tap and let off the throttle, that valve is the cause of it.