When the cease fire is announced and everyone is celebrating, Ho Jon says that he will miss everyone and the Swamp after they are gone, asking for any souvenir he could have. In the pilot episode, though, he was accepted to Hawkeye's school in the states and the MASH staff raised the money to send him stateside also.
The amount of shaving soap on Col. Blake's face changes from shot to shot.
When Radar asks Colonel Blake if he signed Radars scrap-book Blake is shaving and his shaving cream on his face changes from shot to shot.
When Hawkeye and the nurse are kissing in the Swamp, there's a close-up shot of her hands around his neck. All of her fingernails are over an inch long. No nurse would have fingernails that long.
Lt. Colonel Henry Blake is wearing a 1960's to 1972, Rolex Submariner. The Rolex Submariner was first introduced in 1953. The Korean War was from 1950-1953. Considering this would have been around the first year or two of the war, it would have been highly impossible for Henry to have a Rolex Submariner.
Hawkeye calls Brig Gen Crandall Clayton, "Brandell".
In the credits, Patrick Adiarte is credited as Ho Jon. In other episodes he is credited as Ho-Jon.