I had a belly band leak, just to rear of the door. I removed the black band fairly easily (some heat would help so the plastic won't crack). I was able to re-insert it after my repairs. Many of the old screws were rusted and not tight into the wood strip. I bought all new screws, same length but thicker and it did the trick. I think I went from original #8 to a #10 diameter screw.
I used a flexible sealant product called Pro-Flex RV (almond color), which blended in very nicely. I put a dab in each screw hole and then a small bead on top and bottom of C channel. I secured both ends of the black band with a screw, since it had "shrunk" over the years. It's flexible and is back to full size now. The screw top can be painted black to hide it if you like.
My Lil Bigfoot
has been bone dry for 3 years now, even after all the rain & hail storms we've had this year in Alberta. I'll try and attach a picture or two. Not the prettiest fix but dry is more important and it was not expensive.