connection of an alternator .. ??

The positive terminal, which would be B+, goes to the positive terminal of the battery. The negative terminal, which is ground, is the alternator casing. If you want it to charge while running, you have to connect the regulator wire to the pilot light. Or, easier but you have to do it yourself, you can make a jumper from B+ to the regulator terminal. This is just to excite it; don't leave the jumper connected. Regards.

I understand that a bridge needs to be made by inserting a lamp between B+ and the regulator. The problem I have is that I don't know which terminal is the regulator; it has a brown plug and two contacts inside, but I don't know which one corresponds to the regulator.

Hi, maybe this will help you. While you have B+ connected to the battery
and the unit to ground, check which pin lights up the indicator light.
One pin is for the indicator light and the other is the power pin to activate the regulator. If you give me the model number, I might be able to help you with the wiring diagram.