Beginning some major work on my 2000 National Tropical. I need to replace the trim molding that runs horizontally at the roof where the rolled roof meets the side panels. Thought it was similar to a softer vinyl trim that pops into the metal groves by pinching them together like I had in an older travel trailer. This is more of a hard inflexible product and seems like it must be fed in from the end on a track. Have searched the internet, but cannot seem to find what it is called or where I can purchase some. I have found some pictures that might be the stuff, but don't want to order it and find out it is not the right product. Any help in identifying the right product will be appreciated. Thanks.