My own Model 5 story, and perhaps it's just been wishful thinking all these years, is found on an "About Me" page elsewhere on this site. It is reproduced here for convenience.
...after high school I attended two different technical schools for the next three years. Temple University in Philadelphia had a technical institute that taught electronics using examples from the many varied circuit functions found in television sets of the fifties. About the time I was halfway through, they shifted their emphasis from the television set to -- well, it wasn't so much TO something as it was away from television circuits. So I never made that 'senior' course in color TV. The administration had shut it down and I never got my hands on the seven or so RCA-supplied CT-100 sets the school had used in the lab-part of the course. They had been supplied to the school years before by RCA at Camden, just across the Delaware River from Philadelphia. [ I often wonder if they weren't some of the 200 or so model 5s built for the first NTSC color network broadcast of the 1954 Rose Bowl parade. I once spoke to the lab tech about them; it was after the course had been eliminated and the unused sets sat in a cage gathering dust. He told me then that they were not "standard" sets and that RCA did not want them back. ]
Any Temple U. faculty, administration, or students around who can confirm, refute, or add to my speculation?