Hope you don't mind me turning the pic??
The secret to correct posting is in the way the camera was held. It has info on the picture that says which is up and turning the camera 90 degrees next time is one way to set it up. I ran it through Photoshop.
Function of the modern world? We don't always get what we see!
Meanwhile, I would have to ask what you might find in this opening??? Seems too well thought out to just be air venting, so can you feel any sort of release in there?
Any chance of a small mirror on a stick like an inspection mirror to get some view of the back?
https://www.homedepot.com/b/Tools-Ha...toreSelection=
Parts catalog does not give good enough view to spot anything.
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Richard
Why no RV year, make and floorplan on MY signature as we suggest for others?
I currently DO NOT have one!