Hello, Airstreamers! I'm new to the forum and new to Airstreams. We've got ourselves a '74 Overlander in the initial stages of restoration. When the interior skins and the insulation came out, we see what seems to be a section of missing rib just to the left of the door (see pics). There is no obvious sign of repaired damage in that area. Is it at all possible that it is meant to be like this? Hopefully, you will be kind if this is a ridiculously stupid question from a newbie! If it does indeed need to be replaced, please do point us in the right direction. Many thanks.