Hey checked my rivets as I have the vintage bonnet catches and two are not painted as well. Do you think it might be on purpose as between the bonnet catch and the tonneau cover bolts it all seems to work together to me.
I suspect they make all the bonnets the same, regardless of the type of catch/fastener on the order, then just pop-rivet in a washer if the Dzus fastener is not to be used. Seems like they could have a process to not punch the holes if not needed, or at least paint the rivets, but apparently not.