When you get a lot of incorrect codes, suspect the PCM. Like willwren said, check the grounds first. The main PCM ground is on the engine near the oil filter housing. Also, unplug and plug the three connectors on the PCM a few times in case you might have a corroded contact.
Just so you are aware, this is what happened when I tried to fix a random stalling problem on my '95. I had determined after trying nearly everything else that my PCM might be bad. The first replacement PCM (remanufactured and guaranteed) set a long list of codes that were false. The second one from the same company set a bunch of different false codes. The third PCM (from a different rebuilder, more expensive and not guaranteed) solved the problem and set no codes.
If I had replaced parts based on the faulty information from those first two PCMs, I would have spent hundreds of dollars and still not solved the problem.
If you have reason to suspect the PCM, I would suggest trying a different one from a junkyard to see if the problems change or go away. Jr's3800 likes to find low-miles OEMs instead of the remans, 'cause of the problems I stated above.