If you’ve followed along, our 2013 Mustang GT code-named Project High Impact has been the host of several OE derived and Ford Racing modifications. The latest installment on its journey gives it the true markings of a supercar with our 2013 Mustang GT500 Rear Lower Valance and Axle Back Kit. When we started our GT was still wearing its stock rear appointments but we know it deserved something more fitting. We really liked the OE setup on the awesome 2013 GT500 and decided that is what we wanted for our project Mustang! Follow along as we make the transformation. The 2013 GT500 Rear Lower Valance and Muffler Kit will fit 2013 Mustang GT and Boss 302. ** With some modification this kit will fit the V6 model. Due to the differences in the piping diameter you will need to have a muffler shop weld or build you a custom flange to make this kit adapt to the V6′s smaller diameter piping. **
Start by removing the rear plastic panel inside the trunk. It is held in with a couple of plastic nuts and a pair of push pins. Once those are out-of-the-way, lift straight up on the panel to release the clips from the underside. Then you can disconnect the wiring harness and push the rubber sealing grommet through the trunk panel. If you’re like us and really don’t like working around things, go ahead and pull the rear tires off as well.
Move on to the bumper cover and remove the screws at the rear of the wheel well along with the four push pins underneath. With those out-of-the-way the bumper fascia simply pops off. Finish up by removing your axle-back mufflers.
Lay the bumper cover face down on something soft, like an old blanket. Remove the two red reflectors along with the black trim filler from the bumper. Take a moment to prepare yourself to cut on your new Mustang. Luckily, Ford saw fit to bless us with the exact cut lines needed to trim the GT bumper to fit the GT500 lower valance, calming the nerves significantly!
Grab you an air powered body saw and go to work. Follow along the provided line until the lower portion of the bumper cover is cut free.
Then grab you a drill with an 11/32 drill bit & drill holes at each end of the pre-marked tab slots.
After that, finish cutting out all the tab slots with the body saw.
Once you arrive at the fully cut stage, take & deep breath, pat yourself on the back for a job well done, and go ahead and snap the 2013 GT500 rear lower valance in to place.
Before re-installing the finished bumper, go ahead and install the 2013 GT500 axle-back mufflers. They reuse the stock hangers and are a direct fit to the car & the tailpipes.
Finally, hang the bumper cover back on the car. We noticed the rubber seal at the bottom of the tail lights may give us some trouble, so to make it easy we removed the tail lights before installing the bumper.
After the wheels went back on we pulled high Impact out to show her off & get some sound clips. The look is amazing & the sound is even better! For a minor investment of time & money you can transform the rear of your Mustang as well! Check out the finished product & the sound clips!