Vectors to the Sun and Moon

In relation to the shadows cast by the rising lunar major and maximum extremes, and the rising equinox sun,
lines can be drawn from the shadow point on the spiral out to the position of the moon or sun on the horizon.

Theoretically, the intersection of these lines could define the position necessary for the shadow casting edge of the east slab.

Locators were placed at the points horizontal to the center of the spiral where the shadow lines cross.
The vectors in this case crossed at a single point.
The slabs were moved horizontally to meet the intersection point. The slabs were not raised or lowered based on findings from a clue in the shadow.

What are the results when moving the slabs into this position?: