They are Noise filter units, there are two connections on them, the ones you can see in the pic which is engine side and the other connections are on the other side of them through the bulk head. One filter unit is connected in line with the feed to the ignition coil, the other is connected in line between the ammeter and the dynamo regulator. Nice touch to the engine compartment detailing, point to note the holes in the bulk head for the connections of the filter units which pass through the bulk head are about 1/2" in diammeter, this is why they are that size !!!!
There are also two more filter units down the side of the dynamo regulator by the engine side panel, one is the Armature filter unit, and the other is field filter unit.