Correction: Gloria and Mike had already left "All in the Family" prior to the end of that show. Edith remained as a recurring character, although not seen in every episode, through the first season of "Archie Bunker's Place." She died between the first and second seasons and the first episode of the second season dealt with her death. Gloria and Mike came back for one last episode altogether during the first season in which viewers learned that they were on the brink of divorce. Gloria would be divorced by the time the spin-off, "Gloria," premiered.
Mike and Gloria appeared in an episode of "All in the Family" during its last season in which they were on the brink of divorce. Archie, Edith and Stephanie had gone to California for Thanksgiving with the Stivics when they learned of Mike and Gloria's marriage problems. I don't think Mike (Meathead) every appeared in an episode of "Archie Bunker's Place".