Rob, the Pere Marquette car had a four panel Hutchins end. The
vertically corrugated end door on the adjacent auto car was a Murphy
end door made by the Union Metal Products Co. (later Standard Railway
Equipment Co.) This was probably the most common auto car end door
in the early to mid-1920s, before Dreadnaught end doors were
introduced. Union Pacific had them on its A-50-5 class automobile
cars, but the car in the photo isn't a UP car (wrong lettering style).

Richard Hendrickson