The Fantastic World of D.C. Collins was a 1984 TV movie starring Gary Coleman as a precocious kid who imagines himself in all sorts of fantastical situations seen in TV and movies. Improbably, one of the places he sees himself in is...a MASH unit in 1950s Korea!
I'm not even sure where to start with this, it's so unfathomably strange. All I can do is thank Swamp Rat Steve Spatucci for sending it to me, I was completely unaware of the movie's existence. I was happier then.