ISOMAT 1982 CS Shroud cap
I have a 82 cs36T. The spreader caps appear to be pressed and maybe flush rivited to the actual spreader. The shoulds are retained by a 1/4" ss special bolt and bushing which rotates. Mine were siezed and had to be carefully cut out. Then I replaced the bolt with a rubber bush, lanocote and covered the whoe thing with rigging tape due to the unreasonable cost of new spreader boots.
Also I used a rigging guage to check my tensions and found they were very low. I would imagine loose rigging would lead to the shroud coming adrift. Mine were held in place by the rigging tape only prior to the tension adjustment.