Marshall Pass Scrap Trains

I read the Trails Along the Columbine regarding the Marshall Pass line, and was uncertain as to when the final scrap trains operated. Last freight with empty gons west, and empty stock cars east was May 2, 1955.
There are images of 489 doing dismantling work on May 24,195 then I gather from other searches the dismantling trains went on during the summer, and ended around Oct 1, 1955. Can anyone confirm the last day of steam or other dismantling? I see where goose 7 was also used some, but no real details on this in the book. Just trying to determine the end!

Also another question....When was the valley line taken out?
Greg