I don't believe the dovetailed rear sights on the Ruger .22 semiauto pistols are directional. You can make an index mark using a "Sharpie" permanent marker, and give the sight a tap using brass drift and hammer to see. I use Locktite when reinstalling.
Generally, the smaller front sights such as on Mauser military and Enfield miltary rifles, Parabellum and Walther pistols need a sight pressing tool to avoid damage in removal/installation.