Drivetrain alignment and vibration

[npdunn]

Hi there!

Need some help on the following:

I have a SWB 67, 2 wheel drive, 454 w/ 400 tranny.

Issue(s): the driveshaft is not centered through the crossmember (where the trailing arms are attached). I am just curious if it's supposed to be?? There is at least 1/4" difference when comparing each side.

My reason for concern is that I am getting an oscillating vibration starting at 50 mph and it stays no matter how fast you go. I have ruled out the following causes: driveshaft, u-joints, entire rear-end, tires/rims, tranny, flywheel, pinion angles.

My thought is: if the drive shaft should be centered through the crossmember, than the engine is sitting crooked- throwing off everything behind it. Which would also add another angle into the drive-train.

I am possibly stating the obvious, but I would like to get other's opinions.

Thank you for your help! I appreciate it.