'96, 2500, Auto, SC, LB

I seem to have a voltage regulator problem. After starting the engine and operating the vehicle for a bit, the "GEN" light comes on. The voltage gauge shows about 12.5v. Sometimes it varies up to ~14.5v. I believe this is about where it should be.

Because of this, I did the 3 step shuffle to get the OBD code readouts. Sure enough I get a code 47: low charging system voltage. I assume this indicates the voltage regulator needs replacing. Are there other things to check to confirm or is that enough?

To my suprise I also got a code 45: Tranny OD solenoid circuit malfunction. I can't find anything in Haynes or Chilton on this one. Can anyone give me any info about dealing with this?

Clearing the codes then running it around the block puts them right back in giving the same readout.
Thanks for any help 0n this guys.
S V