This is what I ended up doing, before I thought to see what others had been doing with this situation. I looked at the flexible premade stuff with the J-bend gutter that others have posted about, but the largest channel I could find was about 3/4". I figured it needed to be at least 1" of channel to catch the drips\stream coming off the latches which stick out from the sides about an inch. What I ended up using was a 1 1/4 D" channel, widest I could find, then just cut it so it made a J shape. I didn't trust the adhesive that came with the material so I added a side-by-side 1/2" strip of thin 3M UHB tape directly over the existing adhesive (after pulling the protective strip). After applying to the camper I discovered the flexible material would pull in the corner edge in it's tendency to not want to stretch uniformly so I added a short bent 1/2" spine of aluminum stock to keep the width of the gutter around the corner more or less uniform. It works fine to keep drips out of the cab unless it is a real heavy downpour, I couldn't get much slope on the gutter within the limited space so it can simply overflow.