When the door is in place, use a amount to check If your strike-side edge is plumb. If it’s not, make slight changes by pulling the hinge rail out with the jamb somewhat at the highest or bottom. There’s commonly about half an inch of adjustment obtainable concerning these pieces. https://www.deluxeshowerdoors.com/services/glass-shower-door-installation-in-needham-ma-deluxe-shower-doors/