Evaluate And Reduce the header rail. Pull the shower door closed and lengthen your tape measure from just one side to another. Mark the scale around the frame header and use your hacksaw to chop it to dimensions. Sleek down the Uncooked edge utilizing a steel file.[13] X Investigate resource https://www.deluxeshowerdoors.com/services/glass-shower-door-installation-in-needham-ma-deluxe-shower-doors/