69 Barracuda Clutch Shake Help Needed.

Well just to update on this shake situation, I'm still shaking at standing start take off. My efforts had been placed at the rear of the car thus far. I have:

Added 2 then 4 degrees to my pinion angle. Ensured there are no broken welds at the perches.
Fabricated and installed bar clamps on the front section of the leaf springs. The springs already had 2 stock clamps.
Added an adjustable pinion snubber and have that about 1/2 inch form the floor.
Removed my aftermarket rear shackles and reinstalled the stock shackles.
Installed new shocks (old ones were junk) and added springs over those to raise the car rear a bit.
Removed inspection cover and made sure the new pressure plate fingers make uniform contact with the new throw out bearing. Also checked it's operation which appeared very smooth as the clutch is engaged and disengaged.
Checked all motor mounts to make sure they are not broken or loose.
Checked the linkage again for free movement.
Car has a non stock rear sway bar so I unhooked that. Thanks members for clearing that up for me. I thought it was stock.

My next checked was going to be on the rear carrier itself. Before pulling I called DR Diff in Montana. He felt based on my shake only at take off the issue was no where in the rear end area including the carrier.

In my previous posts I mentioned I was going to buy a set of springs. 1969383S, I believe your right on the throwing good money for bad at this. I believe I would have, buying new springs. For now I've decided to ditch that and pull the clutch assembly back out. Now that I've driven the car a bit I suspect a check of the flywheel would be in order.