69 Barracuda Clutch Shake Help Needed.

Just a quick update on my shake issue at take off.

A couple of weeks ago I got the car back on a lift. Had 4 guys and myself disassemble the new clutch setup and reinspect all parts. With a height gage measured the flatness of the flywheel while we rotated that around. It was only out .003. I went ahead and removed the flywheel and had it resurfaced. Friend of mine that owns a very nice machine shop did this and measured the flywheel before completion. This time it was wet ground to make it a bit more smooth than what it was. Inspected the new clutch pad pressure plate and bearing. No issues noted. Before reinstall replaced the front bearing in the transmission while we had it out. Also put a new rear tranny mount in. After all this, still shakes at take off.

I then moved back to the rear. Borrowed an old school set of universal traction bars. Mounted those to the car and made sure the front rubber bumper of the bars was resting against the front spring hanger. drove the car around town here for two days . No shake easing out or dumping the clutch. Tire burnin' machine. I removed the bars just so I could turn this on and off. Back to shaking at ease out or clutch dump. I need to add that the shake is not all the time during ease out. It always shakes dumping the clutch thru this ordeal.

So..... I went ahead and purchased a set of super stock leaf springs. 003's. I opted to put drivers springs on both sides just to make sure I had level ride. Instead of the 002's on the RH side. Car sits great. Raised it up about and inch or so in the rear. I also removed my 4 degree shims I had put in the rear that gave me more angle. In a nutshell though, the car still shakes.

Not sure where to go from here. I do plan to put the shims back but I doubt that is the issue. It didn't help before, however those were in when I had the bars on with no shake.
Evidently the bars band aid the problem. Just have to figure out the cure.

Any brain storming out of the box ideas I'm definitely open to at this point.