i was looking at the stage V website and i saw you can buy hemi conversion heads for your 440 or 383. how do the blocks differ? i ought to know, but i confess that i don't. the bore is listed as 0.10" smaller with the same stroke.

4.25" 3.75" - 426
4.32" 3.75" - 440

are there any other differences other than the bore? and stampings, obviously.