If your Mustang trunk or hatchback rattles it could be that the weatherstrip has compressed to a point to where it isn't holding firm against the trunk lid or hatch. Replace your Mustang trunk or Mustang hatchback weatherstrip with one of LatemodelRestoration.com's quality reproduction pieces.
These parts fit: 1979, 1980, 1981, 1982, 1983, 1984, 1985, 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, and 2009 Mustangs
As a deployed service member, there are not many avenues of contacting companies back home conveniently. Between the time difference and use of wifi or morale phones, it can be challenging. Luckily the team at LateModel Restoration emailed me back quickly and gave me everything that I needed for a smoothe purchase, and a few more that followed. They were quick in reply and quick to help me out and I have my parts on the way to my home now because of it. I will be shopping here primarily and I recommend it highly to fellow Mustang folks.