Analysis of information sources in references of the Wikipedia article "Tetsujin 28-go" in English language version.
The character names were then "westernized": Dr. Kaneda became Dr. Sparks; his son Shotaro became Jimmy; and finally, since there already was an "Iron Man" on the market (see Marvel Superheroes), Tetsujin 28GO was not translated as Iron Man No. 28 but completely rechristened as Gigantor.