To the considerable number of people running searches for this because they saw it mentioned on an episode of History Channel’s Pawn Stars last night:
There was never a plan to build an “Italian Disney World” in the 1960s, or any other time that I’m aware of. Even when Euro Disney was being planned in the 1980s, the final decision was between Spain and France. So, no Italian Disney World. Ever. Do not entrust your theme park history to the cast of Pawn Stars.