The 440 and Pesky Valve Covers

I'm approaching my wit's end. Help!
I've settled on a set of date correct OEM valve covers- had them on for over 2 years- and I continue to have issues with the passenger side always seeming to develop a leak. Tried cork, cork with steel inserts- even composite. Getting tired of the smoke and burning oil smell.
Does anyone have a solution that works? (without having to weld the covers to the block lol)
Author: cv70chall