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After seeing the code list, my thoughts are now that you're either going to be dealing with a bad sensor somewhere on the 5 volt reference B side possibly shorting out internally and taking down everything else, a chafed wire or corroded connector somewhere.....or even a failed PCM. I would ignore the harsh shifting and random no-start at this time, since those are likely just symptoms of the overall issue.   5 volt sensors generally work based on a voltage output to represent a particular value.  Take your range sensor.  It would receive a 5 volt signal, and would output a different voltage to represent PRND321. If the 5 volt signal going into the sensor is being pulled down slightly and randomly by something else, the output voltage will change, and the PCM can interpret those changes as different reported shifter positions. If the vehicle is off and its reporting something other than park or neutral....it won't start. It may also begin shifting funny as it no longer knows which position the shifter is in.  If it were me...I'd be starting my troubleshooting on that 5 volt reference branch first. 

My scanner is a WiFi iPhone scanner.  It is mostly read only.  I could dig deeper into its live reading but all I’ve ever monitored was misfires and temps and very simple PIDs.  Unfortunately that level of scanner is the only one in my budget.  I agree live data would be helpful.     Last week after the first check engine light that included p0651 I cleared all codes and forgot about it and hoped it was a fluke (I can dream).   And then when it started doing the shifting problem I had no CEL and only read codes for the sake of it.  I cleared the second set of codes and hoped it was the heavy rain that day.  (Seriously a big dreamer here) that was the P0742 the first time I believe the last set of codes was after checking the connections at the PCM and DIC and cleaning up the battery connections for good measure.   There was still no CEL on the dash.  We drove it up the frontage road and back as soon as it shifted hard between 1-2   thanks for the ongoing help.   I’ll have much better info when I can get in there more.   Currently not able to work on it due to work.         

Let's start here..........what are you using as a scanner? Is it dedicated OBD2 scanner such as a Matco/Snap-on/OTC? Is it a laptop with a scanner program loaded onto the laptop? You want to clear all of those codes, start & run the car in *real time* (the laptop/scanner connected) & drive until those codes reappear. They're going to be either soft codes or hard codes. Hard codes will not clear until the problem(s) have been solved. Soft codes usually clear after a number of ignition key/engine run cycles & the PCM corrects.

That PO742 doesn't sound, if indeed the TCC is locked due to a fault in either the electronic circuitry, the solenoid passage is mechanically gummed up or the clutch is mechanically locked that'll have a severe effect on the engines ability to try to turn over. If in either Park or Neutral & one tries to start the engine if the torque converter isn't releasing the engine will stall near instantly. In effect the converter is locked up & the converter turbine & impeller will not spin freely of each other. Lock up should only occur in O/D,D & 3rd.  Yes, one has to pull the trans side cover to get at the range selector. That may mean pulling the trans from the car.