Casting P4532134 should be the head, not the intake....If it's the intake, sounds like trouble!

The intake should be casting P4532756 (packaged number P4876127).

Reducing and correcting the chamber volumes via milling on Stage VI's is very common, alot of times they are off end to end so what guys do is mill until the largest chamber was close to whatever spec they're looking for, and then grind out the remaining three to match. Or for more control, mill the whole thing even further and then make all the chambers however they want.

So if the heads were prepped much at all and ccs were changed, I'd suspect they have been milled and the intake fit wasn't accounted for until it was too late. In other words, someone cut the intake (or the intake flange on the head, but probably not, because there wouldn't be any valve cover rail left) too far and then had to use the gaskets to make up for it.