The cables on Cooper Spur go back to when Cloud Cap was the "Timberline" of the mountain. Cooper Spur was the standard route up the mountain, and ropes were hauled up there and fixed for groups to climb up. Since the ropes were so heavy, group sizes had to be pretty large. Classic photos of women in huge dresses going up Cooper Spur are out there.
The materials on the summit are what's left of the lookout. The sign on the lookout is down in the Cloud Cap Inn, along with a bit of the rope that was up on the mountain. I'm not sure how the steel cables come into play.
There is also the old engine sitting down by crater rock, a step back in time. A fun way to go up to it is via the ice gulley bisecting crater rock.