I put the 440 version of that same intake on my car back in 2001. Between the block being decked, the heads being cleaned up and the intake the bolt holes for the intake did not even line up, it sat up too high. I ended up having to remove 0.110" from each face of the intake to get the ports to line up correctly. Just relaying this little tidbit in case you have not checked the alignment of the intake to the heads.
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