Watched Smith Corona 5 Series Typewriter Keyboard Adjustment for Lighter Touch Silent Super by Phoenix TypewriterPhoenix Typewriter from YouTube
This is a fascinating find. Thanks for the tip.
 
In looking at my own ’49 5 series Clipper I notice that the manual adjustment with the H 6-5-4-3-2 L lever attaches to a short spring, then a small plate, and from there to an arm attached to the universal bar. None of the settings on my machine effect any actual change because the entire assembly is loose from start to finish. Your machine in the video does much the same as I can see the spring attached to that lever hangs loose as you move from the L to the H settings.
 
Given the screwdriver settings you’re showing, I’m wondering if that Touch Selector is a vestigial appendage from the 4 Series days? I do notice another nearby unused arm on the universal bar with a hook-like end on it that the spring might have been attached to to provide actual tension. Unfortunately I only have a few 4 series machines to compare with (and their assemblies are dramatically different) and don’t have any other 5 series machines to see what the proper connection setting for the manual touch selector should be.
 
As far as I can tell, no one’s done a proper video of the manual touch selector assembly on the 5 series machines, if in fact they ever worked at all. Perhaps something to add to the list of videos to produce the next time a 5 series Smith-Corona comes through?