If you talk about the same metal pieces what I believe you talk about then
I would say they hold some little plastic rail/guides which always break apart.
These plastic guides/rails should hold the plugwires in position.
When they hang around they get tired and the copperwires break inside.
Isn't it 3 oval shaped metalpieces only ?
Chiltons page 2-5 figure 5
Chiltons page 2-6 figure 6+7
I bet a camel and a bowl of dates the broken yellow plasticparts hang still on your plugwires!