Nothing was done in the plant after stamping the VIN derivative - someone must have done that later. The VIN was stamped, the wiper linkage (and A/C plenum valve, if equipped) were installed, then the cowl vent panel, washer nozzles, and seals were installed.
Here is a photo I've recently taken of my VIN derivative, under the cowl panel, which is still in original paint, and never been removed. I took these photos looking down thru the cowl vent, while shining a bright light into it. You can see that the VIN stamp is corroded, more so than the area around it, and the detailed photo also indicates that dust/mud/dirt over the years has 'cllung' to the stamped areas.
when I saw that, I immediately wanted to do something to 'preserve' that stamp, but I'm unsure what I should do. If it were not for potential judging point losses, I'd remove the cowl panel, gently brush away anything loose, wash away any dust/dirt, and then do a phosphate treatment of the area, followed by a light coat of either black, or clear paint. I would like to show my car in an unrestored/survivor category sometime this year if possible. What do you fellas suggest I do about this area?