Now - the important part - the THICKNESS of the spacers: I would like to say that 3/8" is the optimal thickness. This dimension is critical as this is what will make the car "alignable" within the range of the upper control arm eccentrics. Without the spacers, the wheels will be cocked too far out at the top, and the alignement shop will run out of adjustment on the upper eccentrics (cams) . Ideally, I would like ot have done another conversion using 3/8 spacers before stating categorically that 3/8th is the right width. This I have not done yet. Should you choose to do this conversion, any feedback as to this dimension will be greatly appreciated.