Now that I think about it, vibration only during deceleration should be in the drive-line. You say you have had the rear apart (checked pinion and side bearings). This is a 56 integral rear, correct? It hasn't been upgraded?
If tire balance/out-of-round/ply separation) it should do it at most all times...
I added your 2nd photo (much better appearance
) in the original post.
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- WHY IS IT ... -
... that everything you buy in the grocery store is either wrapped in or contained in plastic but the government doesn't want you to carry it out in a plastic bag?
WONDERING IN W(BY GOD)V ...
DIAGNOSED CDO - (OCD In Correct Alphabetical Order)