I actually have an NOS one in the box, and it is pressed SS, I have two rough ones that are pressed, and another one that is what I believe to be an early takeoff which is also pressed, The early takeoff is particulary interesting as the fellow I bought it from, also had a grill and headlight bezels that were what I would consider early takeoffs. The grill looks like it came from a truck with not many miles that must have been in an accident, as it is riveted, and painted in a way that makes it very original, a perfect indoors stored version of a blue and waldorf white grill.
My take is that the pressed is original, Now with that bit of information, I have seen the cast ones, but am not sure maybe they were made both ways? I am sure about my NOS one as I opened the box.