Hi Richard,
I’ve recently done something like this to my Brum. However, the module that I used (an “A-Reg” from A O Services) also converts the system to 12v and acts as a regulator / rectifier. This changes the system to a two wire system rather like that of a dynamo and removes the need for the light swirch to switch in different alternator coils according to the load. Rather than attempting to describe the connections here if you PM me your address I can send you a copy of the data that came with my system. This not only describes the connections you requested but also specifies exactly which type of alternator is suitable for this conversion. I can also send you the information that Don Payne kindly gave me regarding the jetting and setting up of an Amal Concentric (32mm in my case).
Regards
Roy Fisher
