This is the latest in a series that will track actors from the various Godzilla movies and shows over the years through to Godzilla, Final Wars (2004), the 2014 Godzilla movie being too recent to cover. All known cast members listed. Info derived from imdb. Only roles 2013 and later being tracked.
This animated series, including reruns (hence the 1980 end date despite the show running to 1981) was originally part of The Godzilla Power Hour (1978), then The Godzilla Super 90 (1978-1979), then separate (1979), then The Godzilla/Globetrotters Adventure Hour (1979-1980), then The Godzilla/Dynomutt Hour (1980), then The Godzilla/Hong Kong Phooey Hour (1980-1981), then separate (1981).
Ted Cassidy (Godzilla): died in 1979.
Jeff David (Captain Carl Majors): died in 1982.
Al Eisenmann (Pete): last known acting role in 2012; as Property Master: Criminal Minds (229 episodes 2005-2015).
Hilly Hicks (Brock): last known acting role in 1995, as Director in 2004.
Don Messick (Godzooky): died in 1997.
Brenda Thompson (Dr. Quinn Darien): last known acting role in 1999.
No verified guest cast information found. While Wikipedia lists three, two were people whose careers are generally seen as starting slightly later. If verified (and recurring) guest actors found later, they will be added to expand this list.