Im just a dreamer : 440 vs 360 magnum

I have milled 440 heads 0.100", zero problems [ 0.120" actually ]. However, you would need to:
either mill the intake side of those heads OR mill the intake manifold to get alignment. Best to mill the heads for a couple of reasons. Head is easier to set up for milling, should cost less. If intake is milled, it is married to those heads or thick intake gaskets needed if used with std heads.
0.100" off the head needs 0.140" off the intake side.
Increasing CR increases HP everywhere, while other mods only increase a certain rpm range.