The rub rail is a two part system with a base and insert. The insert should be marked with a pencil on the base and inesert as you want to match up the insert when reattaching it to those marks. There may be a screwed in black plastic piece on the transom where the insert is screwed into place to keep it from shrinking in the base.
Remove it removing the insert.
Go to the damaged area of the base and take out screws enough to relax the base
Then I used a putty blade to pull base off. I had seen some bases that were attached by nut and bolt. Preorder the base from the forum store as they know what is needed and advise how much. Remove old caulk. Cut out old base and replace with new base. You may need to have a few new screws as it may be needed but make sure same length. You will need to caulk and that includes the thread of screws.
Reattach insert by pushing bottom of insert into base and then pushing down top of insert using a flat head screwdriver forcing the top of insert into top of base by using that screwdriver pushing sideways or dragging sideways.
If the insert is damaged, you could put a new section in as well but ends have to be screwed in. As a dealer I put in a whole new insert in which I suggest ordered thru the forum store.
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