I have a '50 COE that came from the previous owner with a '58 235. I have retained a 6 volt system and I believe the distributor is the proper one for the engine. I don't know what internals you would change anyway, except for the condensor. Another factor to consider is the issue of earlier distributors having a hardened gear that would wear the matching gear of the later engines with cast cam shaft. Thus, one would argue against putting the 6 volt distributor in your later 235.

Kent

1937 Chevy 1/2 ton
1942 Chevy 1/2 ton
1947 Diamond T Model 509
1951 Chevy 1/2 ton
1950 Chevy COE Model 5700 ~ "Barney" ~ And more pix