SHOULD I run my 1976 Datsun 180B on regular unleaded or 95 or 98 octane? I'm considering getting a '94 or '95 Nissan Bluebird.
IT'S time time you moved up to something more modern. The Bluebird is fine and won't cost a fortune to fix. Run the 180B on PULP or 98 octane unleaded.