what was the name of the last showed they aired.

...the last episode of William Bendix's "RILEY" series was "Here Comes Constance", originally telecast over NBC on May 23, 1958. {I forgot what it was about, but it was NOT a "farewell episode".}

The last episode of Jackie Gleason's "RILEY" series was the one where Riley thinks Junior won't fight the local bully and tries to give him boxing lessons.
This episode, the 26th and final one of the original series, was first telecast on March 28, 1950 over NBC.....and not repeated until 27 years later!