I have the fancy schmancy CB Performance valve covers with the "life time" silicone gaskets. They are a bit fiddly to be sure you don't pinch the gasket or tighten one side of the cover more than the other and create a leak. Knowing what I know now , I would stay with the bails and the cork.
Also, I have the HD aluminum push rods and was told to use .004 and .005 "snug". Most important that they are the same.
This is why it's madness.
To para-phrase Stan, I are a lineman.