The installation and design of the Sterling 1500D Series shower door has been changed to provide an easier installation experience. The parts kit now includes a drilling template. The drilling template is intended to assist the installer in locating and installing the bottom pivot hole.
If the drilling template happens to be missing from the parts package, you can use the dimensions indicated below to drill the 5/16" hole into the bottom track.
After you determine which side should open, and the fixed panel is installed, then you may use the template to drill the hole.
The bottom pivot hole should be drilled at .500 inches away from the u-channel, and the center of the hole should be centered on the bottom track which is .315 inches from the edge of the track. See the attached image of the Drilling Template for further detail.