Electrical Woes - Bad Alternator/Voltage Regulator

[rhusbands]

I have a 2003 X5 3.0 with 183K on the clock. Last week, my battery light began coming on periodically. It has done so three times. I noticed that it only comes on when I am at WOT and revs approach redline (under hard acceleration). Once revs drop back to normal cruising speed for a few minutes, the battery light goes off. My thought is it is probably the voltage regulator, so I am going to get a replacement and change it out. Will probably get a new battery as-well. Any caveats I should be aware of?

Just FYI... I've only had the vehicle for 4 months, and have no maintenance history on it (other than what I have done... Valve Gasket, Oil Filter Housing Gasket, and Crank Case Vent Valve).

Thanks,

-Ronnie