Big Chevy, I wish I could remember on the vibration with the clutch in. My gut tells me it did not vibrate once the clutch was depressed, but I can't remember for sure. Stuart, yes, this truck has a 2-piece drive line with a carrier bearing. All was replaced. I did notice that the seal at the carrier bearing looks a little off center, but I tried loosening the two bolts that hold the bearing housing and prying it to see if there was any movement. Couldn't find any. Wrenchbender, I used all new tires mounted to the original rims and balanced professionally. I didn't check to see if the floor vibrated when it was jacked up. I'm fairly certain it has to be in the driveline as well, guys, but want to make sure I'm not overlooking the obvious. I'll be laid up for at least 2 months. Had a surgeon break my leg and cut out a wedge of bone. It was that or a knee replacement. That's the fun of getting old. The worst part is not being able to drive the '53!