Leaky Valve Cover Gasket

So I probably have about 500 miles on my engine since the rebuild. The last 100 miles or so I started to notice about a lemon sized oil stain after I parked it. With a little bit of investigating it appears that the valve cover is leaking on the passenger side above the manifolds. It only leaked when the engine was running and generally once it got over 2300 RPMs. The fan blows it all over the place and so it has covered that side of the engine bay. I thought it was a little weird being a new gasket but I accepted that flukes happen.

Luckily I had a spare and put it on. I start the truck, increase the RPM's a little and I can just see it build up along the gasket and then just start pouring down the side of the head. The "newer" gasket is even worse. Now I wish I hadn't thrown away the old original one.

Any thoughts on how to resolve this? It could be seeping from where it touches the head, or it could be running over the gasket through the valve cover gasket channel, or both. My next option is probably a liquid gasket but I don't like that idea because it makes a mess, and if I ever have to remove the valve cover I have to clean it up without it getting any of the silicone into my head, and then redo it every time. I also thought of carefully cutting the spare gasket that I have to be a thinner version of itself and combine the two, with the thinner one acting as a sort of shim to have more pressure once the valve cover is screwed down.

Here is my plan I have a 2.6 that should be ready in the next week or so I plan to assemble the engine on a stand and seal both sides of the gaskets to see if that will help. Asking 2 bolts to hold a valve cover down never did seem like a solid plan to me. It's amazing they were so far ahead in so many areas on these trucks and they come up with a 2 bolt valve cover system.

Sillycone won't "fix" it. I had the same problem until I trashed the Chinese gasket and used American made. Check the pcv, may be too much pressure under valve cover.

I normally run a bead of RTV silicon in the gasket groove, press it in and add another thin bead on the seating face. Do up the rocker cover bolts by hand and let it dry, then tension them up with a ratchet. Good quality RTV silicon usually does the trick.