68 dart window regulator and window install ?

Assuming that you have a 2-door hardtop like my '68 cuda. Looking at the regulator it has a single "arm" coming off the regulator. The regulator has four 1/4" bolt holes in it. Slip the roller at the end of the arm into the small channel at the bottom of the glass and while holding the glass at the top of it's travel - locate the four holes in the doors sheet metal and install.