Vibration in drivetrain

Just another thought.
I had a pretty bad vibration in my driveline when I got the car, and just for the fun of it I removed the front yoke and reinstalled it 180 from where it was.
That did it.
Apparently a lot of people don't know that the yoke should always go back on the same as it came off. (Not turned 180 degrees)

Another little trick I have used to find out what I want to know is to mark the driveline in quarters around it and put a hose clamp around the driveline with the screw on one of the marks, then drive it and see what it does.
It will either make it worse or better.
If it is worse, then move the screw on the clamp to another of the marks and chk it again.
It takes time, but you can figure out which end is out of balance, or that it isn't the driveline at all.