In any old motor vehicle, over time the components can become worn and damaged. If the door window assembly in your 1956 Chevy BelAir becomes damaged, you will need to repair the entire unit to restore it to the best condition. As the vehicle is well over 50 years old, you may have to get in touch with specialist dealers or even with Chevrolet itself to purchase the parts needed for your BelAir.
Open up the door of your '56 BelAir. Use a Phillips-head screwdriver to remove all of the mounting screws attached to the inner door pane. Place the screws in a safe area for reattachment later.
Lift the inner door panel away from the door. Use a wrench to remove the mounting bolts attached to the backing plate on the door.
Pull the backing plate away from the door to gain access to the window regulator. Locate the bolts that connect the window to the window regulator. Use a wrench to remove the bolts. Lift the window pane from the door of the BelAir.
Remove the lower mounting bolts attached to the window regulator and lift the regulator away from the door. Place a new regulator onto the door so that it is just below the door's window frame. Fix the regulator in place by attaching the previously removed mounting bolts onto the bracket of the regulator.
Insert a new window pane into the door frame. Line up the bolt holes on the window with those on the window regulator. Connect them together by reinserting the mounting bolts between the two. Place the backing plate back onto the door and secure it in place by reattaching the mounting bolts using a wrench.
Lift the door panel back onto the inside of the door. Use a Phillips-head screwdriver to reattach the door panel mounting screws.
