Background art credit from "Sam Savitt Checklist" in Illustration Magazine (The Illustrated Press, Inc., 2002 series) v1#4 (August 2002).
Inside front cover.
Photographs from the television show.
A television adaptation.
In his interview in The Art of Al Williamson (Pacific Comics, 1983 series), George Woodbridge states he was the artist on Gray Ghost. Woodbridge stated he consulted with John Severin on what kind of uniforms, guns, and other items to use in the artwork (information via Stephen Palmer via the GCD Error Tracker # 11773, reported 3 August 2018).
Jerry Bails' Who's Who and Alberto Becattini's 2007 Dell Four Color Comics Checklist states the art is by Ray Bailey (American artist).
Inside back cover.
Art credits from Alberto Becattini 2007 Dell Four Color Comics Checklist.