These are basically three clip-shows of the 1967 - '73 original, interspersed with segments from the press conference for the 1993 Anniversary Special (
http://www.imdb.com/title/tt0296837/). They might even
be the Anniversary Special broken into three parts. So far, I've spotted a GMC "Old Look" and an early Econoline.
Tell ya what, I'll get captures and post 'em to this thread. Y'all can decide from there.