The castor arms where they connect to the upper control arms allow a bit of play even when they are brand spankin' new, mabe that's what you're seeing/feeling?
It would be kinda like the top edge of the tire can sort of roll in and out a bit while pivoting off the bottom edge.
Drift to the left is usually not a good sign of a proper alignment or can indicate among other things bad tire pressure balance. ('other things' being those of a potentially much more serious mechanical nature)
Most alignments are commonly done (unless you specify otherwise) so the car either tracks straight or drifts to the right (the US anyway) so that if you doze off you drift sort of gently off the road, not into oncoming traffic.
It would be kinda like the top edge of the tire can sort of roll in and out a bit while pivoting off the bottom edge.
Drift to the left is usually not a good sign of a proper alignment or can indicate among other things bad tire pressure balance. ('other things' being those of a potentially much more serious mechanical nature)
Most alignments are commonly done (unless you specify otherwise) so the car either tracks straight or drifts to the right (the US anyway) so that if you doze off you drift sort of gently off the road, not into oncoming traffic.