Measure the metal channel of the existing trim after removing the existing trim, and set the new trim into place by pressing the trim into the metal channel. Rubber trim is typically fastened with one or more screws.
To remove the trim quickly, place a finger on the metal channel, and press the trim upward along the channel to release it. If screws hold the trim in place, remove them and set them aside. Clean the metal channel with a scrub brush to remove old caulking or debris.
Cut the starting end of the roll of molding to straighten it, and place the trim onto the metal channel. Pinch the trim slightly in the middle to insert it into the metal channel easily. Follow the metal channel, pressing the trim downward after inserting it to set it into place properly. Cut the trim at the end of the metal channel, clean the screws, and replace the screws.
Apply a recommended sealant around the screws and on the cut ends of the trim, and check the trim periodically for signs of damage. Replace cracked trim immediately to prevent damage to the underlying materials. When replacing rubber trim, replace the entire piece of trim rather than replacing small sections.