Marshall Pass turntable history

I've heard that Marshall Pass started out with a 50-footer that at some point was replaced (and went, I believe, to Ridgeway). By 1923 there was evidently a 62-footer in residence. I've also found references to a 67-footer, but with no date.

Is the 67 a typo, or was the turntable replaced twice? If so, anyone know when the second upgrade happened?

Also, does anyone know the timing of the snowshed designs? I have pictures of both a round, conical-roofed structure over the turntable, and a more squarish lean-to-type arrangement. But I don't know which order they came in, or when the transition happened.

(I've a copy of Bourneman on order, as well as the relevant Trails Among the Columbines, but it will take some time for them to get to me on this side of the pond.)

Thanks for any assistance,
Jeff.