AXMAN - "I can find nothing showing John Wayne's connection to "Gunsmoke" ..."
Axman, in 1955, when CBS was going to air the first episode of "GUNSMOKE," John Wayne was the person who introduced the show in a brief prologue to the show. He also introduced James Arness as "Matt Dillion." I've seen that short clip many times, courtesy of CBS.
John Wayne was NOT in any of the episodes, thereafter.
"GUNSMOKE," was the longest running network dramatic series in the history of television. 1955-1975.
FWIW.
L.W.