While cleaning out his parents' attic Sunday, Mark Norton, 24, stumbled upon a Welcome Back, Kotter spec script written by his father, which has apparently lay dormant in a box labeled 'keepsakes' for nearly 30 years. 'I never knew Dad to write anything, but there's his full name, address, and telephone number right on the cover sheet,' said Norton, adding that the script had all the cast members taking a trip to Hawaii, a place his father has always wanted to visit. 'But why didn't he do the gag with Mr. Kotter telling his wife a joke about a distant uncle? That show was canceled before I was born, but even I know that.' According to Norton, he read 15 pages, then carefully placed the script back into the box and walked over to the attic window where he watched his father, dressed in cutoff jeans and a baseball cap, hedge the lawn for 20 minutes. 