My 56 came with the factory TS switch and system. I have seen numerous 55's with and many without. I have also seen
several 57-59's without.
However, this is by no means a scientific sampling or representation. Some buyers felt they needed them, others did not.
I have seen trucks that came with the factory switch that someone wired around with an aftermarket switch as well.
Not sure when the states mandated turn signals, probably about 1960.
Fred
