Ok, I sort of figured it out. I will unstar my answer for a better one, should it arise!
The diagram in my original post is the answer, I just did not understand it.
1) first set your arms with 0 Ackermann - the the drive and slave* arms will be parallel (shown by the dotted lines)
2) Calculate your Ackerman the same way you would with rack and pinion - it is the angle from the center of your rear axle to a front wheel.
3) Now subtract your Ackermann amount. This will open the angle of the drive arms (shown with the solid lines)
4) Wow that worked!
However this only provides ONE correct solution, out of an infinite number.
The arm's "straight" setting can be swung forward and backward, so long as they are parallel.
the radius of the arms can be different on the drive and slave*. This can be used limit the steer sensitivity, but affects the correct compensation.
So in the end I say: use the method I describe, along with the image in the OP, then use the spreadsheets to experiment with other solutions. I also found a program called "Solve Space" which I have not dug into yet, but is free and can simulate linkages.
*If there is better terminology, do let me know.