[Walt Fricke]

1) Agree that if you go to all this trouble, you should slot it so you can raise/lower the pivot as theory and testing and whatnot show will optimize things. Of course, if all you are doing is moving the outer pivot (spring plate) up so you can lower the car more without screwing up something, you'd increase the inner mount the same amount.
2) When I bought a car with adjustable inner mounts, I thought I was in alignment hog heaven. You could adjust camber without really affecting toe enough to worry about (assuming you didn't go from one end of the range to the other). But it seems you should set these so the roll center is where it is best, and adjust camber in the usual old way (which, with 935 spring plates, can be a lot easier than with the stock setup).

I used to lust for the double A arm type of suspension, thinking you could optimize things. Turns out there is no free lunch - Carroll Smith shows that even with this setup - the most used on full on race cars - there are trade offs.