Hi Steve!
The "range" aspect is limited by the throttle idle-stop, and the WOT stop on the bracket. If you have the spring set to the highest (furthest from fulcrum) position, the amount of throttle throw required to go from idle tension (on the spring) to sufficient tension to reach maximum governed speed occurs over a very short range, hence, a person would have to screw the max-speed stop WAY in to keep from exceeding revs, and the throttle control would be so touchy, it'd be more or less on, or off.
By moving DOWN the throttle side, closer to the fulcrum, the WOT stop can be backed out, and the throttle will have a more trimmable 'range'.
This assumes that the person doing the adjustment used the proper spring, didn't have cable-travel-throw problems, had the governor arm properly sync'd, and had the 'sensitivity' selection point located in such a way that the governor/spring relationship was actually functioning.
I believe the gentleman that posted indicated that he actually HAD governing, just didn't have the ability to control the full range, even with the idle stop correct, and the max-speed stop screwed all the way out. At the time, I posted that I suspected he had an incorrect spring length, and upon finding a longer spring in my parts-box, I did a test swap on Loader-Mutt, and found that it exhibited the characteristic which he indicated.
As an experiment, I tried re-orienting positions, stops, etc. to get proper governing AND full throttle range, and it just wouldn't do it. Upon reinstalling the shorter spring, it jumped right back into line.