Complex sentence: In 1963 it was again renamed Corio "North" Post Office when the contemporary Corio Post Office inside of the Corio Shopping Centre was opened, which is now located on the ground floor, having moved from its original first floor location.
Split into simpler sentences: In 1963 it was again renamed Corio "North" Post Office when the contemporary Corio Post Office inside of the Corio Shopping Centre became open. That Post Office is now located on the ground floor, having moved from its original first floor location.