If the PCV hose is "dry", then that probably isn't the problem. It's too bad the exhaust manifolds are such a PITA on a Hemi to remove, if you have excessive oil past the guides you should see it on the back of the exhaust valves. Likewise on the intakes which you should be able to see with one of those cheap boroscopes by pulling a carb. As to the spark plug tubes, I'm no expert but my buds that run 2nd Gen Hemis say a common problem with spark plugs is that owners don't remove the gasket on the plug before installing them. The tubes are intended to be the gasket.

But what do I know.