you can adjust the strike of individual typebars by either filing or peening the ring-stop tab, file to hit harder & peen to lighten it. for your situation, you will want to file the ring-stop down a bit; make sure to tilt the machine up(or on its side) so the debris created doesn’t fall down into the pivot segment, then blow the area out with compressed air. if you go to Hobby Lobby or an RC model shop, you should be able to get a cheap set of needle files which will do the job; follow up with 600-800 grit sandpaper to remove burrs

roller pliers are for adjusting the height of individual letters(increasing the arc to lower & decreasing arc to raise, which in extreme case can then require adjustment of the slug to put it ‘square’ again relative to the platen) adjusting the strike for most models is done by either filing or peening the ring-stop tab near the base of the typebar(as is the case for OP’s smith corona)