Drive train vibration. Scratching my head.

My thinking...

1. If the engine at the same RPM creates the same vibration sitting still in the driveway it is engine / trans.
2. If it happens while coasting in neutral, engine ideling but still moving at 55 to 70 it is drive shaft, rear end related, or tires / wheels.
3. Both could be trans to some extent.

What I posted earlier was meant to be the above.