To assemble the window with a ventilator, first remove the door trim panel and inner panel water deflector. Secure the window in the fully up position using adhesive tape or by wedging two pieces of 3/4-inch heater hose between the window and the door frame. For 2-door vehicles, take out the inner panel cam by removing two bolts. Next, remove the ventilator division channel's lower adjustment stud and nut, along with the window regulator attaching bolts. Press the ventilator division channel outboard to disengage the regulator spindle from the inner panel, and slide the regulator balance arm roller out of the lower sash channel cam at the front. Remove the regulator through the large access hole, and installation is the reverse of removal. For window assembly without a ventilator on 1973 and 1974 models, follow the same steps as above. For 1975 and later models, follow the initial steps for window assembly with a ventilator, then drive out the center rivet pin and drill out four regulator attachment rivets. When installing the new regulator, attach it to the inner panel with screws and nuts, placing a J-nut over each attaching hole in the back plate where there are clinch nuts. Finally, replace the inner panel cam, water deflector, and trim panel.