Section 6. A town may, at a town meeting, vote that official ballots as defined in section one of chapter fifty shall thereafter be used therein; and may, at the annual town meeting or at a meeting held at least thirty days before the annual town meeting, by a two thirds vote rescind such action. In town elections at which official ballots are used, nominations for town officers elected by ballot shall be made, ballots and other apparatus therefor provided, and elections of such officers conducted, in accordance with chapters fifty to fifty-six, inclusive, so far as applicable.