Yes, it was I, who posted the laser gizmo and here it is in use.

Photo 1) The gizmo. A laser tool with swivel head.
Photo 2) The head set at neutral position to check the stab center line.
Photo 3) The head swiveled to the right to check alignment. Measured at 30 degree angle.
Photo 4) The head swiveled to the left for a perfect matching 30 degree angle.

Purchased this at Carr Hardware years ago and it has become a necessity to me. Extremely accurate and more dependable than a piece of string and easier than a measuring tape.