The suspense is OVER......
Personaly, I prefer to use an external stand alone charger (MAHA). However, if you are so inclined to charge internaly, here you go. I found this online so I can not say if it works or not:
"Black" Battery Holder Modification
If you don't have a stand alone battery charger for your extra rechargeable batteries, or you've lost or broken the yellow battery holder, you can modify your radio to recharge your batteries with the black holder. Remember, don't plug your radio in if you're using alkaline batteries in the black case after completing this mod.
Open the battery door, and remove the batteries and holder.
Remove the four screws located on the back of the case.
Carefully pry the back half of the case off.
Locate the three metal strips at the bottom of the pc board on the right hand side.
Locate the two strips spaced closest to each other, and solder a jumper to these two strips.
Reassemble the radio in the reverse order you disassembled it.
You will now be able to recharge batteries using the black holder. Again, use only rechargeable batteries with this mod. If you attempt to recharge non-rechargeable batteries in your radio, you will cause the batteries to leak or explode.
Manny