Another update to the vibration quest. I had the DS checked at another place and they said it was .030" out, I had them fix it and reinstalled, no change. I rotated the shaft 180*, no change. I had the car 4 wheel aligned and the drivers rear was out by 3/16". shimmed it, no change. The car drives better than it ever has- im just fighting the vibes. I replaced the rear poly trans mount, no change. I replaced the passenger side poly mount with stock, no change. When I drive it down the road at 60-70 and kick it to neutral the vibes go away. When i rev the engine in neutral there are no vibes, When I put the car on jack stands and run it at those speeds its there. I removed the exhaust clamps from the tips, removed the muffler supports and set the exhaust on blocks, no change. Added weight to one of the pipes, no change. I dial indicated the wheels, axles, brakes and driveshaft on the car at the trans it has .019", at the center of the DS-.005" and at the pinion, .013". To me the shaft is still out. I have the car on stands today and with everything turning the vibes are there, when i pull the DS out and run it in 3rd gear and rpm no vibes:banghead:. Technically after 3 DS (original, new one built, new one supposedely fixed) by the measurements it looks like I need another driveshaft. Im down to DS, trans, or rearend. I also have a vibration app for the Iphone and it picks it up with the shaft in you can see the cyclic vibrations and when the shaft is out it goes away.