Now I am facing the electrical system of my 1928 M2 Rugby. I have seen headlamps chart of Mazda bulbs and there is some indication about 32 and 21 CP for 6Volts. Looking around locally I found 50 CP bulbs and had been told that those where the lamps used at that time.
My concerns are
the size of fuse required
the type and function of the external coil (or resistance) shown in electrical diagrams in manuals posted in the Club, technical page 91 of the 40 model, that is external to the light/ignition switch.
Ricardo: The designation of CP stands for Candle Power. When your car was new it would have had a 32 CP bulb if you lived in a state which allowed it. if you can get a higher CP bulb you should be able to use it if you have good wiring.
The wire coil you refer to is a resistance coil and it lowered the amp to you lights when the current went through it which in turn gave you a dim light. Most antique cars do not need dim lights so if your restiance coil is bad I would just bypass it. Several other options are to wire up a dual filament bulb and add a dimmer circuit or find a replacement. Most cars of your vintage used a similar set up and the restiance coils are avaliable. Modern resistors are avaliable if you want to experiement.
Hope this helps, Jan