I was talking about an adjustable strut/locator bar OR the upper control arm. Any way you do it, moving the control arm moves the ball joint, that is what you are doing when you move the control arm. The alignment is simply the location of the upper and lower pivot points, if you move the upper or the lower control arm, you move the upper or lower ball joint/pivot point.
That is how you get the alignment, by moving those ball joint locations.
I couldn't find any adjustable Mustang II but found earlier Mustang ones.
I have no idea why I put "real", it's a sarcastic remark of mine about things like "real" parts stores. It wasn't needed there because I love those little Mustang II's!
But many cars and trucks the lower control arm moves with eccentric washers or even just slotted holes. Simply loosen up the bolt, move the arm over and tighten it back up, the rear of a Saturn SV1 does this as an example. Many late model cars have an adjustable lower control arm very much like this one with the strut rod, the bushing at the crossmember has an eccentric washer that pushes the control arm in and out to get the camber desired. The lower ball joint is being moved in and out to get that camber.
Most A arms like on a Chevy truck have upper and lower A arms with full eccentric adjustment top and bottom.
I am worried about this SAI because that means that an inner pivot point has been moved in or out some how without effecting the caster or camber being all that those are real close.
How can the SAI be off 9 degrees! The only answer is the inner mounts are different from one side to the other along with a bent spindle or different mounting points at the inner side of the control arms!
If this readout had included "Included angle" we would have a lot better idea. But something is seriously screwed up.