MerCruiser 470 170hp 3.7L 4cyl Starter Motor Assembly 50-72550A1 1973-82 9-Tooth Flywheel I am not quite sure

I am not quite sure what it's from but KB4 & KD4 is my best guess at this time

9-Tooth Starter

Also Used on the Ford 2

but I don't see why not)

missing paint

MerCruiser 470 170hp 3.7L 4cyl Starter Motor Assembly 50-72550A1 1973-82 9-Tooth Flywheel I am not quite sureItem Details Removed from a 1976 1978 MerCruiser 470 Tested & Working Parts Included Starter Assembly 50 72550 50 72550A1 50 72550A2 9 Tooth Starter Prestolite MHA 7016 Compatibility Used only on EARLIER MerCruiser 470 Models using this type of starter. 1976 1982, but please check your serial number. The 1983 & beyond models used a significantly different looking starter. 1976 1977 1978 1979 1980 1981 1982 Alpha One 470 4 cyl 170hp 3. 7L 224CID