69 Z on e-bay

[CamarosRus]

Regarding painted door latches.....I'm in the process of replacing a reskinned door with a good Original on my 69. I had the original, media blasted after removing ALL the guts. What would the professional restorers apply to the zinc plated latch assembly in the way of grease/cosmoline to replicate what the factory evidently did.
On any of the Original paint cars, you can almost always see where paint has been worn/washed away as it was over the factory coating of ????????
Any body care to share there thoughts ???????