My buddy has a 1992 325i Automatic (build date 9/91) and the alternator appears to be going bad.

Is it possible to replace the brushes and regulator? or should we replace it entire alternator.

On a good note I recently replaced my entire cooling system in my 535i M30. New radiator, radiator clips, radiator mounts, thermostat, thermostat bleed screw, water pump, belts, coolant tank, coolant cap, hoses, and BMW coolant. Parts were about $600 from BMA.

Thanks,