Code 67

That is what it showed for it. Since I have my motor out tonight I will look since it should be easy to find. I can't find any info on testing the switch or a close up to confirm that, that is correct. Although the price seems to be right according to All Data.

Maybe someone else can chime in, if they know, you have me curious now.
 
Ok so the top sensor on the LH side of the Trans is the Backup switch. The NSS or Clutch switch (Depending on what book you are looking at) is on or behind the clutch petal arm under the dash. This is what Alldata states as far as testing.

This switch functions magnetically. Do not use magnetized tools near this switch.

1. If the switch is open when the clutch pedal is released, speed control will not operate. This must be corrected before making any other tests. Use only a voltmeter of 5000 ohm/volt rating or higher when performing the clutch switch test.
2. Disconnect switch pigtail connector from speed control harness connector, then connect an ohmmeter to the two switch connector terminals.
3. With clutch pedal in the fully released position, the resistance should be less than 5 ohms. With clutch pedal fully depressed, the circuit should be open.
4. If switch does not function as described, remove and replace switch.

I was going crazy because depending on what book or reference you are looking at it is called something different. But seems the part is reference to the clutch switch, which will throw a 67. As far as the code 15 I would clear the codes and try again. I am not sure about using that computer with the swap, since I have not done that before, or if it is the cause of the 67, but hopefully this helps a little. I wouldn't think the 67 would throw the MIL, but maybe so.
 
The switch on the top of the trans is an NSS but it's not required to start the car. It's only used to tell the computer the trans is in neutral and to dump codes. If it was faulty, you wouldn't be able to pull codes.

Check the one on the pedal. Can you start the car without pushing the clutch down? You removed the jumper and plugged the harness in correct?