1963 Valiant differential rebuild kit and ring and pinion gears
May be able to help with part numbers.
2070023 and 2070025 were used from 1960 thru 1965. They never superseded to a newer number.
2070596 has a long supersede history.
2070596 - 1962 - 1963
2467132 - 1964 - 1965
2743204 - 1966
2643204 - 1967 - 1970
Each number supersedes to the following number.