As Caroline is waiting to be connected with Mr. Morang she is seen from the side looking at a good-sized monitor that has a microphone mounted just over the top of the monitor, to pick up Caroline's voice the crew that sending her image and voice to Mr. Morang. When the camera angle changes the microphone is gone.
The honor detail that brought Neil's remains into Union Station was in dress whites. But we were assured that it was on Valentine's Day, February 14. The Navy wears blues in February, even in San Diego. The honor detail should have been in dress blues.
In the opening scene where various servicemen are getting ready to board the train, the marine uniforms have post-WWII enlisted rank insignia. The marines did not use the crossed-rifles device in rank insignia until many years after the war.
The song that the couples are dancing to at the end of the movie is Dream a Little Dream of Me being sung by Doris Day. Doris Day did not record her version of this song until 1957.
Multiple vintage automobiles are shown during the WWII flashback scenes. Gasoline was rationed then and cars were required to display ration stickers on their windshields; none of the cars have them.
The scene where the man is working on a tractor. The distributor he is working on is from an air cooled VW motor, not a tractor.
American flags shown in WWII flashback scenes were modern 50-star flags. During WWII, before the admission of Alaska and Hawaii, the American flag had only 48 stars, arranged in simple rows and columns.
Caroline sprays Neil with a sprayer pistol on the end of a garden hose. But sprayer pistols like those did not appear until the 1960s. In the 1940s, small cylindrical sprayers were used.
During the fighting in the Philippines, the weapon used is an M1 Carbine. They are using 30-round mags which did not come into use till the Korean Conflict. The Carbine itself is correct.
The version of "Dream a Little Dream of Me" that was heard on the radio during the World War II flashback scene was a recording sung by Ella Fitzgerald and Louis Armstrong. However, this particular recording wasn't released until 1950, five years after the war ended.
Morang repeats Neil's last words before he died, to Caroline. But Morang could not possibly know what Neil said in his last moments, because he was alone.