Hi everyone. Last year we purchased a 1980 Coachman 210 Deluxe that has been really taken care of. Now that we've been able to take it out a little more, I'm starting to replace some little things that have been neglected over the years (like external covers and such). Can anyone tell me what this "slot" is for? It goes over the door and runs the length of the popup. I suspect it has something to do with an awning (which we don't have, yet (hopefully)).