When I installed my intake I read all the instruction carefully. In regards to the gaskets normally placed between the ends of the manifold and the block, Edelbrock said to only use High Temp RTV Silicone and if on the block there were gaskets already, to remove them.

My manifold was leaking oil at both ends. Today we pulled it back apart.
Much to my surprise I found out why.

In the picture below you can see where I placed 1/4" beads of Silicone the length of the block at both ends, to me it looked just as it was described I should do. Here was the surprise, the Silicone looked just the same as it did in this picture, was not flattened out pressed down in any way. Just as it was when I laid it down, only set up of coarse. The manifold had never touched them, no wonder it was leaking!

I could not find Edelbrock set of gaskets (like I purchased before) locally so I bought a OEM set and they came with 1/4" thick cork end seals.
We installed them and we will see if all is well tomorrow. I'm just at a loss for as to why it was recommended to use silicone and not the end seals like we have now????

 

It can be done either way, Your bead of silicon was not thick enough. Brand of gaskets doesn't matter. How does the manifold sit on the engine? do the bolt holes align up

 

Yes they line up okay, so I think it's going to be okay.

I was also a little thrown as to the head gasket tabs and if they were to
lay flat under the end seals?
I hope so because that's where they ended up.

 

When you use the stock cork end seals the head gasket tabs go through the slots in the cork end seals...if I use them I always run a small bead of black RTV right in the corners where the head tabs go throught the cork...
Black RTV has to be two to three passes high to work...it has to be thicker than those cork end seals...I used the cork this time for the original factory stock look..