How could you forget that? That was the biggest thing that year. I saw a gif of the system on "X" the other day and it was a simple cam shaft triggering three microswitches. I actually find that hard to believe because a simple transistor circuit could do that. I was 16 and really into cars at that age. Never could afford one, so I drove the family second car, a 1962 gray VW Bug.
What can I say? I don’t remember anything in particular about that car’s taillights, so if they were sequential, it must not have struck me as unusual.