Or better put, what do I need to do to change my flex plate?

 

You could unbolt the transmission and torque converter then slide it back. What's wrong with the existing flexplate?

 

You can change the flexplate without removing the transmission. Remove the engine. One or the other must be removed to change it.

 

That's what I was picturing (hoping for).

Not sure that's the problem but hoping it is. I heard a clunk then no matter what I did the engine just spun.

 

Is the transmission output spinning?

 

No it's not unfortunately. I can hear something at the torque converter whizzing if I lock it up (via switch) but nothing else and no power.

 

Well, your starter ring gear is on the flexplate. If you can still start your truck, the issue most likely lies inside the transmission or the torque converter, not the flexplate.

 

Just took off the inspection / bolt-up cover for the flexplate/torque converter and the flywheel and torque converter are both spinning with the engine.

If I engage the TCC lockup clutch, I get a zinging/whizzing sound that I never got before. Could that mean I have a torque converter or maybe fluid pressure problem?

For anyone wondering about their flexplate... you can check it easily by removing ONLY the cover.