Check your AOAI Magazine Issue #60, page 15….A letter issued by Lewis Minkel of the Studebaker Corporation, and reprinted by noted Studebaker/Avanti expert George Krem, reads…..(QUOTE)
”Effective October 1, 1963, and until further notice, all new and unused Avanti models, when first sold at retail and licensed or titled after the October 1, 1963 date, will carry the registration year designation year 1964.”
The above referenced document, originally issued in 1963 by Studebaker Corporation, indicates (to me anyway) that the correct answer to this trivia question is 10/1/63…. Ed