The wheels shouldn't be crabbed because if the p'hard rod! All this will adjust is the sideways movement of the rear axel the more you lower the car the more it shifts! Measure it before you start a piece of wood across the arch and measure to the centre cap do the same on the other if it's the same set it to the same length as standard if it's nearer the n/s make it shorter! You won't feel any difference in the alignment! Hth Rob