Oil puddeling on intake manifold .Factory 273 4bbl duel exhaust

Check your intake bolts. Take one of them out and look at it. If it is saturated with oil thats your problem. The intake bolts are open to oil and will actually wick oil up onto the outside of the intake. You already know this. Either use ARP thread sealant or Permatex on the bolt threads. You can use RTV type sealant but I'm not a big fan of it getting into a engine. I just got finished installing new heads and intake to my 360 and used ARP thread sealant.

My 273 was the really bad about the oil coming around the intake bolts.
Then try new valve cover gaskets.