Can internally regulator alternator work in car with external regulator?

Yes, an internally regulated alternator can work in a car with an external regulator, but modifications to the wiring may be necessary. The internal regulator in the alternator would need to be disabled, and the external regulator would need to be connected to the alternator in its place. This may involve modifying or bypassing the existing wiring, so it is important to consult a qualified auto technician or refer to the specific instructions for the external regulator to ensure proper installation and functionality.