Last year I aligned 4 cars using the Longacre gauge. The first was my red car and yeah, I had to add spacers between the lower ball joints and knuckle to get adequate negative camber.
I sure don't know all the answers and I cannot claim to be properly trained in automotive stuff. I jump in and figure things out while sometimes getting help from others along the way.
It looks like with the alignment cams adjusted for maximum caster, if you need more negative camber, you have to give up some caster to get there.
To recap...
The left side aligns better than it did with the stock UCAs (with offset bushings).
The right side aligns FAR worse than the stock control arms and these PST arms.
Trying to be reasonable here but how could THAT be blamed on the installer or sloppy factory tolerances ??