Even though the Thales Simplicity is a pivoting tangential tracker with its own idiosyncrasy, you can still align it using traditional methods. You can use a typical paper template or protractor to confirm alignment. Since there's no overhang and supposed to be tangent, then wherever the stylus on the template the cantilever should be 90 degree pointing to the spindle. Typical template has two points on the arc, inner groove and outer groove. Draw additional lines on the template to confirm you have more than just two points are tangent.
You can draw your own template: find the effective length (Thales published a nondescript "9 inch") which should be the distance between the left armwand's headshell pivot to armbase pivot, and draw an arc from base pivot to spindle and draw multiple lines intersect with the arc and then draw perpendicular lines double distance all the way back to the Thales triangle. Voila, you have yourself a template you can use to confirm alignment. This way, you don't have to blindly follow the headshell alignment jig.
Bottom line is to have the cantilever always perpendicular (90°) to the radius or pointing to the spindle. In a traditional pivot arm, you only have two tangent points but the Simplicity is tangent on every point.
See GIF so you get an idea.
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