The dog tags that are worn are Vietnam-present style with no notch on the side opposite the chain. WWII and Korea tags had a notch which was used to line up the embossing tool.
When BJ opened the boxes the Depressors were packaged in poly bags.
Clear polythene didn't appear until after 1965.
When the sergeant delivering the truckload of tongue depressors opens the tarp on the back of the truck to reveal the dozens of boxes to Col. Potter, there is no binding holding all of the boxes in place. And with the truck filled right up to the back, many of those boxes would have fallen out of the truck on the way to the 4077th.
When Hawkeye is walking with B.J. across the compound, Hawkeye can briefly be seen wearing bright blue '80s Adidas tennis shoes.
Klinger, Captain Allen, and a Stars and Stripes photographer are walking to be introduced to "Ben". The group walks past an empty cardboard box with a recycling symbol printed on its flap. The symbol was not created until the 1970s.
A Stars & Stripes photographer of the day would shoot with a rugged, made in America, Speed Graphic or Crown Graphic 4x5 camera, not the small, expensive German Hasselblad which this shooter has around his neck.
During construction of the monument, Col. Potter asks Hawkeye to be sure to "save a couple of tongue ticklers for the customers." However, a rough estimate shows that approximately 250 tongue depressors were used to cover one side, which means that the monument is constructed of perhaps 1,000. With 500,000 on hand, not only is Col. Potter's concern of Hawkeye using up too many tongue depressors utterly unfounded, but the 4077th would still be stuck with practically all half-million of them.