This is a most interesting article. It has ultimately prompted me to search for the highest-quality AI-S zooms, for reversing purposes, rather than the lowest-quality.
According to Nikon literature, and your close-up, the 36-72 mm has a maximum reproduction ratio of just under 2:1 (1.8x), not 3:1.
To get to 3:1 (12mm on your ruler), you'd need a 20-24mm lens, reversed.
The 35mm lenses fluctuate from 2.1x (17mm on the ruler) to 1.8x (20mm on the ruler), according to Nikon literature, as well as clip you posted, depending on the model.
That said, I have ordered a 28-50mm Zoom-Nikkor f/3.5 AI-S (which offers 2.5x to 1.1x lifesize), the 28-85mm Zoom-Nikkor f/3.5-4.5 AI-S, which offers similar, as well as the 25-50mm Zoom-Nikkor f/4 AI-S, which offers 2.6x to 1.1x, when reversed.
This last lens is, by far, the most expensive (and the largest), but supposedly it has the best quality, with almost zero CA, as well as the broadest macro range, reversed.
Time will tell, but this article here is what prompted my interest in a field-adjustable zoom, so thanks for writing it.