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Installation Instructions for 70224: Seat Rail Extender Kit for 1999-2004 Mustangs

Don’t be cramped when putting your horse through its paces! Installing our Seat Rail Extenders repositions the seat 4” further to the rear, providing tall drivers and passengers additional legroom. Requires one kit per seat.

Kit Includes:

  • 2 Seat Rail Extender
  • 2 1-hole Backing Plates
  • 4 10x1.5-40mm Hex Head Bolts
  • 6 10x1.5 Nyloc Nuts
  • 10 3/8 Washers
  • 2 spacers

Required Tools:

  • Basic hand tools
  • Drill and 13/32” bit

Install Time:

  • Approximately 1 hour

(Please read all instructions prior to beginning installation. Call the JEGS tech line if you have any questions.)


  • Remove seat from vehicle. Keep all mounting hardware, as some will be re-used during installation process.
  • Position front hole of Seat Rail Extender over factory stud and loosely secure to floor re-using factory hardware.
  • Place 10mm bolt, washer and spacer as shown in Fig.1 and fasten into rear factory mounting hole. Tighten both front and rear bolts securely.
  • Repeat procedure for second rail.
  • Re-install seat and position front seat track mounting hole over second hole located in Seat Rail Extender. Using the factory bolt removed from rear mounting location, insert bolt and washer from top side and loosely secure with supplied nut and washer. Repeat for second rail.
  • Slide seat forward on tracks to access the rear mounting location.
  • Using rear hole in the Seat Extender Rail and seat track as a guide, drill through the floor pan with a 13/32” drill bit. Note: Before drilling, confirm area is clear on bottom side of car.
  • Using supplied hardware, insert 10mm bolt and washer from above and secure with backing plate, washer, and nyloc nut under car. Repeat for second rail and tighten all bolts securely.

Customer q:



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Posted on
May 10, 2018
Instruction Guides

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