EXACTLY what I did to my driver's side rustang II mount. The rubber insulator came "unglued" from the top plate. These mounts have a pin all the way through the mount from the factory with a bushing on one side. The bushing wend bad and allowed just enough movement for the top plate to tear loose from the rubber insulator. The insulator was still in fine shape. These mounts are very hard to come by. No one makes them new. They are the only factory mount that will work with V8 Pinto and Bobcat swaps. So, I cut the end off the factory pin and drove it out. Then replaced it with a carriage bolt, a sway bar link bushing and a locknut. Obviously, it's the mount on the right. This can be done with pretty much any biscuit style mount.