Chevrolet Repair: 1995 z34 electrical problems, industrial electrician, stem turn

Question
I have a 1995 Monte Carlo z.  It has 84K original miles.  I recently replaced the battery because the car would not start.  I also had to have the stem (turn signal/cruise control) replaced.  Since then I have not been able to keep the car running.  The battery will maintain a charge of 11.8 to 11.94 volts (I'm an industrial electrician by trade) but when started and placed in gear drops to 9.2 volts then stalls.  If I leave the car in neutral it will stay at 11.8 volts.  Help!  Please!

Answer
The charging system should be at 13.5 to 14.0 volts checked with a standard voltmeter with the car running. If its running less than 13.0 volts, your alternator is not charging the battery. Running the vehicle like this will cause (as you probably already know) low voltage situations across the entire electrical system causing weird things to start happening.