OK, so I 'think' I fixed it myself.
The camber link was fine, so I started looking at the toe-in, this IS adjustable, here's what I did :
1. raised and supported rear on jack stands, removed the wheels.
2. clamped an "L" channel aluminum bar to the left rear brake disk at the bottom, put a level on it and measured 3 feet back from the center of the spindle and marked it.
3. Hung a plumb bob down the center of the rear using a strong magnet (on a microfiber towel ) holding the string to the spoiler. ( the string centered on the Chrysler logo and the point molded into the center of the bumper cover.
4. Measured from the 3' mark on the bar level to the string : 28 1/4 "
NOTE at this point : the left tire shows completely even wear, so I am assuming the toe-in is correct on this side.
5. moved the same setup to the right side and measured 27 3/4 ", which means the tire was pointing out at the front. This explains why my roadster always hunted to the left.
I could not take my hands off the wheel to fasten my seat belt without it wanting to head out in the front yard.

6. I stood a pointer at the end of the bar for reference and adjusted the toe by loosening the 18mm nut and turning the T55 bolt.
7. Once this side also measured 28 1/4", I clamped it all down and remeasured.

I am still going to take it in and get the alignment checked, but I think it will be pretty close now.

( It was the 'cupping' on the tire that led me to think it was a toe-in issue, not a camber issue )

using simple math, .5 / 36 * 100 = 1.38 degrees : the amount the toe in was off on the left rear wheel.