What is the best intake gasket for a SBC with Holley 300-36 IM?

I have been doing some research about what style gaskets to use with aluminium intakes vs Steel. I bought a set of felpro intake gaskets 90314-1 from autozone and found out I might not be able to use them. It looks like they have a steel laminate core. I spent hours researching if these were actual steel cores and keep hitting dead ends. In the 90314-1 instructions it doesn't say what type of intake material is required to use them on. What exactly is the reason you can't use steel core gaskets on a aluminium intake? Also, if I can't use these then what part# should I look for? I don't want to have the take the intake off again lol. From what research I have done, what about these felpros 1256? http://www.oreillyauto.com/site/c/de...0584&ppt=C0226