If I remember right the factory used like a two sided adhesive rubber strip type stuff. Mine came right off, but if it didn't I had plans of using the heat gun to warm it up really good, try this it should help alot.
When I put them back together I used 3m black weatherstrip adhesive. If you over-do it a little don't worry, you can let it set up then cut the excess of with a razor. Good luck, let us know how it worked.