IIRC, the factory used a stud/nut in the bottom hole, and a bolt in the top starter hole. On automatics, they also had a cooling line bracket on the bottom stud too.
I believe it varied. I have seen them as you describe, but my 64 Valiant has the stud on top. When I got the car it was that way and had not been touched, still with the original starter in place.
