BB Intake Gaskets

So I bought the intake gasket set for a 383 and it came with the aluminum piece and 4 cork intake/head gaskets.
I am running a weiand high rise, do I need to use all the gaskets?
If not, how does it seal with just the aluminum piece, and what's with the 4 gaskets?
The guys at the parts store had no idea.

And here is a random pic:

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