After the door is in position, make use of a stage to examine When the strike-side edge is plumb. If it’s not, make slight adjustments by pulling the hinge rail out in the jamb a bit at the highest or bottom. There’s generally about 50 percent an inch of adjustment https://www.deluxeshowerdoors.com/services/glass-shower-door-installation-in-needham-ma-deluxe-shower-doors/