Ii hope this reaches 'gossjh'. I didn't follow up on this thread back in 2019 like I should have. I saw the one person's reply that the step I was asking about could have been from a Model H or HA. Now I see your post, My step has underside bosses also. Your comment about guides for brake rods explains some of my questions. Is there any chance you could send me a photo of your car that would also show the step. I would like to place a photo by this step in my collection.
Thanks, Ernie
cchopper@centurytel.net