Hi Steve,
I think you're talking about these Dzus Fastener plates, but they mount to the engine bay sheet metal. They do not keep the fastener from falling out of the trunk tub, rather they are what the fastener secures against when inserted through the holes in the trunk tub.
To remove the tub, each fastener is turned a 1/4 turn and removed from the trunk.
So where did you find them inexpensively? I'd like to get some because mine look, pretty ratty - surely less expensive than re-plating mine.
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