How to Install a Racing Seat and Harness in Your Mustang

How to Install a Racing Seat and Harness in Your Mustang

Last Updated April 12, 2024 | Meghan Drummond

As you improve your Mustang’s suspension, engine, and ability to grip the road, the factory seats become a weak point. That’s when you know it’s time to upgrade to a more serious racing seat. With a high-performance bucket, harness system, and five-point harness, you’ll be more prepared to go fast and (just as importantly) brake fast.

You can also expect to see huge weight savings. Factory seats can weigh over 100 pounds. The Corbeau FX1s weigh around 57 pounds, including the adjustable brackets. In our 2004 Saleen Mustang, we reduced our weight by 53 pounds by upgrading to the Corbeaus. A fixed mount bracket would improve the weight savings even more.

To install your race seat, you’ll need to purchase a bracket that’s designed for the seat and your vehicle.

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Selecting a Racing Seat

There are a lot of great racing seats available. When selecting one, there are a few things to keep in mind.

Rules and Regulations

If you plan to participate in motorsports, make sure the racing seat you buy complies with the sport’s regulations. Some sports require the use of a roll bar or a seat back brace.

Fortunately, national organizations make their rules available online and are easy to research.

SCCA Rules

NHRA Rules


To operate as intended, a racing seat needs to fit properly. Here’s how to measure yourself so that you get a great fit.

Seated Hip Width - Sit on a table or workbench with a rectangular object on either side of you. Then use a tape measure to get the distance between the two objects.

Shoulder Height - While seated, assume the posture you expect to have while driving. Then measure from your seat to the top of your shoulder.

Illustration showing proper race seat measurements

Street, Strip, or Both?

If you want to take your Mustang to the strip but also want to drive it there instead of trailering, then there are a few things to keep in mind.

Seat Belts - In order to be DOT compliant, you’ll need to keep your regular seat belt intact. Fortunately, wanting to drive your track beast home isn’t uncommon, so most seats will have a way to install a harness and keep your seat belt. In our install instructions below, we keep the original belt in addition to the five-point harness.

Comfort - Even the very best racing seats aren’t always the most comfortable. Especially if you’re a little larger. Make sure to measure for fitment carefully. And be honest with yourself. If you prefer long group rides and road trips, maybe a super firm racing seat isn’t as good a fit for you as a performance seat with a few more comfort options. Check out our Mustang seat replacement guide for a more detailed list of available options and considerations.

Passengers - If you want to install a harness bar, you can’t really have backseat passengers. It should go without saying, but having a steel bar at face level isn’t a good idea in terms of safety.

Installing Your Racing Seats

Installing racing seats, a harness bar, and a five-point harness will take about 3 hours. If you’re only installing seats, then it won’t take quite as long. Many people opt to install these three items together because of their compatibility.

In our example 2004 Saleen Mustang, we went with Corbeau’s FX1 Pro seats, five-point harnesses, and harness bar system. Your parts may differ based on the seats you pick, but the basic installation process should be similar.

Tools Required:

  • 3/8" Ratchet
  • Short Extension
  • 1/2" Socket
  • 11/16" Socket
  • 15 mm Socket
  • 17 mm Socket
  • 18 mm Socket
  • 7/32" Allen Key or Bit
  • 3/8" Allen Key or Bit
  • T50 Torx Bit
  • 15 mm Wrench
  • 17 mm Wrench
  • 5/8" Wrench
  • Drill
  • 1/8" Drill Bit
  • 7/16" Drill Bit
  • Safety Glasses

Remove the Existing Seats

  1. Remove the front bolts.

    Bolts in the front of a Mustang Seat

  2. Remove the rear bolt covers.

    Removing the rear bolt covers on a Mustang seat

  3. Remove the rear bolts.

    Removing the Mustang's rear seat bolts

  4. Tilt the seat forward.

    Tilting the seat forward

  5. Optional: If you're removing a power seat, then you'll need to remove the plug from the bottom of the seat where it connects.
  6. Unplugging power seat cable

  7. Lift the seat out of the vehicle.

    Removing front seat

Remove the Seatbelts

  1. Remove the upper bolt cover. To do this, slide your finger behind and pull out on the corner.

    Removing upper seatbelt cover

  2. Remove the bolt.

    Remove bolt

  3. Remove the plastic wasther.

    Removing plastic washer from seatbelt

  4. Push the bolt out of the receiver.

    Bolt is pushed from the receiver

Install the Harness Bar

  1. Put the collar on the bolt.

    Collar is added to bolt

  2. Put the bolt and collar through the factory seat belt harness.

    Bolt with collar is inserted into factory harness

  3. Wrap the seat harness over the top of the harness bar.

    Harness is wrapped around bar

  4. Insert the bolt through the harness bar opening.

    Bolt is inserted through hole in harness bar

  5. Place the washer on the rear of the harness bar.

    Washer is placed on rear of harness bar

  6. Screw the bolt into the factory location.

    Bolt is screwed into factory location

  7. Remove the lower seat belt bolt from the rocker.

    lower seatbelt bolt is removed from rocker

  8. Remove the thick factory washer to create more space.

    Thick factory washer is removed

  9. Remove the plastic sleeve from the lower seat belt.

    Plastic sleeve is removed from lower seatbelt

  10. Take the lap belt and overlay the openings.

    Lap belt is overlayed and openings matched up

  11. Insert the bolt through both openings.

    Bolt is inserted through both openings

  12. Add the bracket for the harness bar.

    Harness bar bracket is added

  13. Secure the lap belt, factory harness, and harness bar bracket to the rocker panel with a bolt.

    The lap belt, factory harness, and the harness bar are secured to rocker panel with a bolt

Install Support Bars

  1. Secure the top of the support bar to the harness bar (only hand-tighten for now).

    Top of support bar being bolted to harness bar.

  2. Secure the bottom of the support bar to the rocker panel (only hand-tighten for now).

    Bottom of support bar being bolted to rocker

  3. Thread the locknuts at the top and bottom towards the center of the bar.

    Threading locknuts into harness bar

  4. Once the process has been repeated on the other side, everything can be tightened down.

    Tightening Harness Bar Bolts

Prep the Racing Seats for Installation

  1. Remove the receiver from the original seat.

    Pro Tip: If you’re removing the driver’s seat, you’ll notice a wiring harness for the fasten seatbelt sign. Simply unplug and remove the harness with the receiver.

    Original seat's receiver is removed

  2. Add the factory receiver to the Corbeau bracket.

    Receiver is attached to the Corbeau bracket

  3. To add a submarine belt (recommended for most motorsports) you’ll need to drill a hole in the new bracket. Use a ruler to find the middle of the center bar and mark it.

    Marking center bar for drilling

  4. Drill through the marked location.

    Drilling through mark made in center bar

  5. If you’re installing a 5-point harness and keeping the factory harness, you’ll need to drill a pilot hole.

    Pilot hole is drilled

  6. Once the pilot hole has been drilled, use wider drill bits to open the hole up more.

    Using a larger drill bit to widen pilot hole

  7. Use bolts, nuts, and washers to secure the harness belts.

    Harness belt is secured

  8. Remove the hardware under the seats to attach the track.

    Hardware is removed from underneath the seats

  9. Slide the track either all the way forward or all the way back. This is necessary to access the bolt locations that line up with the seat.

    Seat track is slid forward to access bolt locations

  10. Place the bracket on the bottom of the seat and line up the holes.

    Place bracket on bottom of seat

  11. Secure the bracket and seat together with bolts.

    Bolting bracket to seat

  12. Slide the track to the back (or the front).

    Harness bar bracket is added

  13. Secure the lap belt, factory harness, and harness bar bracket to the rocker panel with a bolt.

    The lap belt, factory harness, and the harness bar are secured to rocker panel with a bolt

Install the New Seats and Harnesses

  1. If you’re using a harness bar, you’ll need to remove the included hardware on the shoulder straps of the harness.

    Removing harness hardware

  2. Pull the harness through the buckle.

    Harness is pulled through buckle

  3. Wrap the shoulder strap through the loop.

    Shoulder strap is wrapped through loop

  4. Thread the loose end of the strap through the bottom of the buckle.

    Strap is threaded through buckle

  5. Repeat Step 4 for all three shoulder straps.

    Threading shoulder straps through buckles

  6. Screw the bolt into the factory location.

    Seats are bolted into factory locations.

  7. Thread the shoulder straps through the provided openings.

    Threading shoulder straps into place.

Enjoy Your New Racing Seats

Once installed, your new seats and harness should keep you securely planted no matter how curvy the road ahead of you.

If you’re working on a motorsport-specific Mustang build, check out our other resources for modification ideas.

This article was researched, written, edited, and reviewed following the steps outlined in our editorial process. Learn more about CJ's editorial standards and guidelines.