Thanks to SleuthTV, I caught up with a sequel reunion movie from 1989, a year before I began dabbling in the Toobworld concept. "The Return Of Sam McCloud" had many of the old faces from the show - Joe Broadhurst was now Chief of Detectives, Peter B. Clifford was the NYC Police Commissioner, Chris Coughlin was living in London and working for the London Times, and Sam McCloud was now the junior senator from New Mexico.
Mention was also made of Sgt. Grover, who was living in Florida and fishing with his grandchildren. (Grover is the link between 'McCloud' and 'Galactica 1980'. The actor who played him, Ken Lynch, sadly passed away a few months after the TV movie aired, in February of 1990.)
The TV movie also gave me an interesting theory to link 'McCloud' to 'The Immortal' and to 'The Wild, Wild West' with the main villain of the piece, William Maitland.
Maitland was the elderly head of Chemtel, a grasping, vulture-like multi-millionaire who was not above murder in order to keep hold of his company's fortunes. And it didn't bother him at all that he was suppressing research that could save thousands of lives.
I think William Maitland was related to Arthur Maitland, the dying multi-millionaire from 'The Immortal'. Arthur Maitland wanted to make Ben Richards his prisoner so that he might have access to the unique properties in Richards' blood which basically made him immortal.
It could be that Arthur and William were brothers, and that they both made their fortunes with Chemtel. And their interests in scientific research that might extend the average life of a human could perhaps be traced back to an ancestor who was obsessed with finding a cure for the "Sedgewick Curse". "The Night Of The Sedgewick Curse" referred to a rapid-aging disease that afflicted the members of the Sedgewick family ('The Wild, Wild West').
There yuh go!
There were many other Maitlands in Toobworld who could have been added to the family tree, but you should never push the connections too far, even in a world of identical twin cousins!