Some info I have come across.
There are something like 12 different casting and numbers for big block Mopars. The changes between them are pretty mild between the different numbers, such as a slight port change, exhaust valve size, and slight changes in combustion chamber size. They all have the mounting holes with some exception back in the '50s. Closed chamber heads were very early, like pre-1964(ish), exhaust valve enlarged around 1968 because the 440s couldn't clear the exhaust fast enough, but otherwise, they all port to the same amount, and of course the extra cooling holes extra lowering of the compression with extra metal around the spark plug area, about 2cc larger combustion chamber area, along with the extra water "triangles", and that's about it.
Other may know more and well versed in this matter.
Big-Block Mopar Engine Block Casting Numbers
1944929 – 1958, 350 B-series big-block
1737629 – 1961-1964, 361 B-series big-block
1851629 – 1961, 413 RB-series big-block
1851729 – 1959-1964, 383 B-series big-block
1852029 – 1962, 413 RB-series big-block
1852029 – 1962-1963, 413 RB-series big-block
1852029 – 1962-1965, 426 RB-series big-block
1945429 – 1965, 361 B-series big-block
2120229 – 361 B-series big-block
2120329 – 1959-1960, 383, RB-series big-block
2120429 – 361, B-series big-block
2120529 – 1959-1965, 413, RB-series big-block
2128854 – 1964, 361/383, B-series big-block
2205697 – 1959-1965, 413/426 RB-series big-block
2205712 – 1958-1966, 361B-series big-block
2406730 – 1963-1965, 426 RB-series big-block , Wedge/Max Performance Wedge
2432230 – 1964-1966, 426 RB-series big-block, Wedge/Max Performance Wedge
2440873 – 426 RB-series big-block
2468030 – 413/426 RB-series big-block
2468130 – 1959-1971, 383 B-series big-block
2468330 – 1964-1965, 426 RB-series big-block
2468330 – 1966-1971, 426 RB-series big-block, HEMI
2532130 – 1965, 383 B-series big-block
2532230 – 1964-1966, 426 RB-series big-block, Wedge
2536430 – 1966-1972, 440 RB-series big-block
2568130 – 1959-1971, 383 B-series big-block
2658836 – 426, RB-series big-block, Commercial
2658930 – 1965, 361 B-series big-block
2899830 – 1970, 383 B-series big-block
3614230 – 1971-1972, 400 B-series big-block
3698330 – 1973-1978, 440 RB-series big-block
3698630 – 1973-1978, 400 B-series big-block
3698830 – 1972-1978, 440 RB-series big-block
4006530 – 1976-1978, 400 B-series big-block
4006630 – 1975-1978, 440 RB-series big-block
426 Hemi Engine Block Casting Numbers
2468330 – 1964-1971, 426 Hemi