OK, update again for anyone who is interested.

It is a pet peeve of mine when someone asks a question then doesn't follow up with what they did to solve the problem, so I am trying to not be that guy.

I was able to figure out how to read codes on the "Check engine light" by counting the flashes.

I did not disconnect the battery after changing the Throttle position sensor.

Here is what I have:
12, 45, 51, 27, 15, 24, 32, 55

According to what I can see online, this is what I have found.
12: Direct battery input to PCM was disconnected within the last 50 key-on cycles.

45: Governor pressure solenoid circuit. **
or
Overdrive solenoid circuit. **
or
Governer mid-pressure malfunction. **
or
Governor pressure sensor volts above rated volts. **
or
Governor pressure sensor volts below rated volts. **
or
Transmission relay circuit. **
or
3-4 shift malfunction. **
or
Governor low pressure malfunction. **
or
Governor pressure sensor. **
or
Overdrive switch low. **

51: A lean air/fuel mixture has been indicated by an abnormally rich correction factor.
Side note here** When the truck was running, I was attaching and disconnecting vacuum lines to see if it made any difference. I think this is why this code was thrown.

27: Fuel injector not responding.

15: No vehicle speed sensor signal detected during road load conditions. **
or
Low output speed sensor RPM, above 15MPH.

24: Throttle position sensor signal does not correlate to MAP sensor. **
or
Throttle position sensor input below the minimum acceptable voltage. **
or
Throttle position sensor input above the maximum acceptable voltage. **

32: An open or shorted condition detected in the EGR solenoid circuit.

or

A mechanical problem found in EGR system (vaccum line leak, defective EGR valve, plugged EGR tube, etc.).

55: Completion of fault code display on Check Engine Lamp. (end of codes)

I think the first culprit to investigate would be the injectors since the truck is having a miss. Anyone agree with this logic?

eightlitermopar