Every dimension is wrong (block, deck, bolt pattern, head, length, cam, valves) except crank journal diameters, but the cranks can't be exchanged.
The oil pump looks like it can be swapped, but since the 1955 Gen-2 pump is even bigger no one has tried in 60 years. The distributors may swap?

The basic stovebolt head design was good enough for Mercedes to use until 1971 in the 280 SL ("pagoda" roof), and the post-WW2 Toyota Type “F” L6 OHV engines are based on this head.
I disagree, vertical OHV valves were made obsolete in 1949 by Cadillac and Oldsmobile (and eventually Ford SB, FE, FF, Chrysler LA, B, RB, Pontiac, Buick nailhead, Chevy SB, etc.) flat chamber floors are a terrible idea. The highly rated "H" head's chamber is almost completely open with no squish. The "D" chamber has quench but badly shrouded and placed valves.