Depending on what area is giving problems and it's an early dash, know that Ford/DeTomaso addressed this issue while the Pantera was still in production and released a series of black trim pieces that penetrated the shrinking vinyl with tiny nuts behind the dash to hold the upholstery. It's described in TSB Bulletin 5, Article 31. I have recently seen such a complete NOS kit at a vendor's shop (rare!), or you could probably rig a duplicate at home, if you are handy with tools.
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