Assembly line artifact find

[EXNODRAMANOTCH]

Tonight after removing the driver's side sill plate & lower seat belt bolt in preparation for replacing the door weatherstripping I found a 6" x 6" metal plate with "DSO POLICE" written on both sides. The side that was up was painted the body color over raised hand painted lettering and the down side was painted a primer color with raised hand painted lettering, which was then drawn over with what appears to be a yellow ink pen. From the color of the floorpan under the plate I can tell that the car was painted with that plate just lying back there. I thought one of those assembly line plates might be under the carpet because when I first got the car & stepped on the footwell area behind the driver's seat a muffled metal moving sound could be heard. A neat piece of history to find. A not so neat piece of history to find was the mouse nest in the passenger side rear seat cushion bottom.