TMI Upholstery - Ford Mustang Parts Replacing the upholstery is only fixing half the problem when restoring your seats. Adding new seat foam will restore the correct shape and density to your seats. This part is a must when reupholstering your seats. TMI offers both standard and premium replacement seat foam for 1965-2007 Mustangs, all available from CJ Pony Parts. Order now! to our YouTube Channel to see more videos!!