Mark Houlahan
Tech Editor, Mustang Monthly
May 1, 2001

Step By Step

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When that red chevron lights up at night, it’s an unmistakable look indeed that says, “Look out, I’m coming over!”
Removing the ’94-’01 door panel is simple. If you have the Mach 460 audio system, carefully pry off the speaker grille to the tweeter assembly to aid in clearing the door panel.
Pry out the switch panel with a small screwdriver, remove the screws attaching the window switches to the panel, then set the panel aside. Next, remove the screws found under the panel that was just removed.
Remove the plastic trim bezel that surrounds the inside door handle and set it aside as well.
A plastic retaining plug is at the front of the door (at least on our ’99 Cobra). Pry this plug out with a trim tool or other similar tool.
Before removing the door panel, apply the appropriate length of duct tape to the underside of the Mach 460 tweeter assembly. This housing has sharp edges and therefore can cut the vinyl-wrapped door panel. Lift the door panel straight up and off of the door shell to access the mirror wiring.
Remove the three screws that hold the Mach 460 tweeter housing in place (if applicable), then remove the four screws that retain the main door speaker in place. Disconnect both speakers and set them aside to allow for ample room to work.
Disconnect the electrical connection for the side mirror, then remove the wire retainer from the doorskin. Now remove the three metric nuts that retain the mirror, then separate the mirror from the door shell.
Use a heavy towel or wear a pair of work gloves to separate the mirror glass from the mirror by prying the glass out of the mirror housing from the outer edge.
Sometimes the electric mirror pivot ring will stay attached to the mirror glass and will need to be removed separately after the glass has been removed from the housing.
After reattaching the pivot ring to the motor arms (arrows) and reseating the dust seal around it, the mirror housing is ready to accept the new turn signal mirror assembly.
Begin the installation of the new turn signal mirror assembly by transferring the foam backing from the old glass to the new turn signal glass.
Using the correct wiring harness (the driver side will receive the short harness) for the side you are working on, connect the harness to the turn signal glass assembly.
In order for the turn signal harness to enter the car, it will have to pass through the mirror motor harness. Make a small incision into the harness cover on each side of the mirror body grommet, then pass the harness through the grommet as shown.
Leaving enough wiring behind the motor for movement of the mirror glass, you can now snap the new turn signal mirror glass into place by using your palm (flattened) and either a towel or work gloves for protection.
Remount the mirror to the door shell, passing the factory harness through the sail panel to the factory wiring plug. Next, route the new turn signal wiring down inside the door, through the doorjamb wiring harness boot, and into the kick panel area.
Remove the kick panel and locate the correct wire for the left or right turn signal circuit in the kick panel. The instructions included have the color code and connector location marked.
Instead of using the butt splice connectors supplied, we used a quick splice terminal that accepted a male spade terminal (for easy disconnects for service or repair). A self-tapping screw made a quick ground nearby.
Reassemble your door panel and wiring connections. Install the Mach 460 tweeter grille cover last.
Before moving on to the other side of the car, check your power mirror for proper operation and full movement in all directions. If everything checks out, you can duplicate the steps shown for the other side.
Now when someone is in this ’99 Cobra’s blind spot, he or she will get an additional warning that the driver is about to initiate a lane change. This simple project can be performed in your driveway with basic tools; the results speak for themselves.

Here's an update in the mirror safety and styling department, but this upgrade concerns the outside rearview mirrors.

For several years Ford has created one version or another of turn signal mirrors installed on various models (mostly trucks and SUVs) from the factory either as an option or as part of a package group. These signals were either embedded in the mirror glass or were an integral part of the plastic mirror housing. Having a turn signal midship is akin to the turn signal on a semitrailer. If you're in the driver's blind spot and that midship turn signal blinks, it lets you know that the driver is about to move into your lane and that you should take the appropriate actions.

We wanted the modern convenience and safety features found on other Ford vehicles to be installed on our own Mustang. We turned to Classic Design Concepts for its new turn signal mirror conversion kit for our '99 Cobra coupe. The installation takes a little more than an hour and requires basic metric tools and wire cutters to complete the job. The finished look is near stock (you can see the LED chevrons if you look closely, and there are CDC logos on the glass), and the safety improvement is dramatic for the Mustang and its inherent blind spot.