Gruber (Carl Ballantine) actually only died a few short years ago. He lived to a good old age. The guy who played Virgil died about a year ago or so, as did Borgnine himself.
I guess the only ones from the show still surviving are Tim Conway, the guy who played Fugi, Gavin MacLeod, and the hillbilly character Willy (who was the real-life son of husband-wife country superstars Kitty Wells and Johnny Wright, if memory serves me).
One of the crew members was the son of one of the Johnny and Jack country singing duet. It has been so long, I can’t remember...