The following images may help you tell if the automotive record-player you are thinking of buying is the authentic, factory-equipped item provided by Chrysler Corporation or an aftermarket addition.
Columbia 16-2/3-RPM Highway Hi-Fi (from 1956 through 1959)
This model was an extra-cost option starting with all 1956 Chrysler products.
Front view, installed under dash, with front door closed.
Same unit, official factory photo.