I do not know about gooseneck hitches, but I do know about the 54/55st TBRT Engineering hitch (it might be out of stock - discontinued). It fit perfectly in my 1954 3104 pickup. It is strong and well-made. But, I'll have to hang my rear license plate elsewhere?

http://www.tbrtengineering.com/classic-towing-products.html

It looks like they will sell out what they have in stock, and make no more.