A Complete Guide to Replacing 1965 Ford Mustang Headlights – Industry Mag industrymag.org

1 Access the Headlight – Open the hood and locate the back of the headlight assembly. The headlight is secured by a trim ring on the front and a retaining ring inside the engine bay.
2 Remove the Trim Ring – Using a Phillips head screwdriver, remove the three screws holding the trim ring (bezel) in place. You don’t need to remove the screws completely—just loosen them enough so you can rotate the trim ring and lift it off.
3 Remove the Old Headlight – With the trim ring removed, the headlight assembly is free. Gently pull it forward from the front, reach behind it, and disconnect the wiring plug. Set the old unit aside.
4 Prepare the New Headlight – If you’re installing H4 conversion headlights or LED units with separate bulbs, you may need to make minor modifications. Some installations require enlarging the center hole on the headlight bowl to allow the new bulb to sit properly.
5 Connect the Wiring – Plug your new headlight into the factory wiring harness. For basic halogen replacements, this is a direct connection.