Never found any overspray of white on the surface facing the trunk compartment though have a number of originals with what appears to be white paint drips or smears on those surfaces that may be the results of the removal of a mask or something else used to block paint during the process.
Will see if I can post a couple of those in the meantime for examples of unrestored ones guess you have looked in the unrestored picture thread area and those pictures already. You can used examples from other plants, focus on Dearborn in this case, since they likely had the same supplier. Also there was just a discussion about the paper labels and the taillight housings last week or so where I posted some pictures also