Svengoolie,” who, in the spirit of Halloween, spoke to The Post about the part he’s played for the past 44 years.“I used to use a fake mustache that I would have to stick on with spirit gum [adhesive], and under the hot [TV] lights it would come off so I would add more spirit gum,” said Koz (pronounced “Koze”).“I remember going to my dentist and he said, ‘Something is wrong with your mouth.’ It turned out I used so much spirit gum that it leaked into my mouth and affected my gums.“I was always a big fan of Groucho [Marx],” Koz said, “so now I paint on the mustache.” Koz, 71, inherited the Svengoolie role from creator Jerry G. Bishop and hasn’t looked back (he was originally known as “Son of Svengoolie”).