2 Books Found

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" Looking for an old book from my childhood, but I can't remember its name or author. A slice of life book written for kids in which a man collects garbage, pretending each piece is an alien. It was listed as Sci Fi; in some instances, but most of the story treated the man like he was delusional. He turned out to be right, but not until the end of the book, when the disguised aliens really did take off in a spacecraft made of technology and a crew that had been disguised as junk. "