Thank you for that clarification, awsmone. I see what you describe in the bottom photo. Looking at that photo, to me, it appears as though the red laser line is slightly thicker on the left front edge of the cartridge than it is on the right front edge. In other words, the cartridge looks like it needs to be rotated clockwise around the zenith angle for proper alignment. I assume you want the left edge of the red laser beam to run along the center line mark on the protractor because it looks like the two lines do not overlap but rather touch along their edges.
I think more important than lining up the front edge of the cartridge to the laser is to look below the cartridge body to see if the cantilever is properly aligned and parallel to the lines on the protractor. Cantilevers are not always perfectly aligned inside the cartridge body, so it better to go by the cantilever angle/edge than the front or side edge of the cartridge body. Then one should confirm by listening.