A new dynamo must be polarised when fitted to the car, before connecting the wiring harness. This may be achieved by connecting a length of wire from the non-earth terminal of the battery to the small (field coil) terminal on the dynamo for five seconds.
Currently one exchange specification is offered, encompassing the above into a unit without the extra cover band and fitted with Lucar terminals. To fit this to a pre-TS60000 car with screw connections on the wiring harness, items 20 and 21 will be required along with your new dynamo.