I have no idea about your particular model....
but I'd suppose you likely have a door or window on that same wall. Open it and measure.
Mine are fairly thick...if memory serves something like 2 to 2-1/2 inch ballpark.... I just don't remember exactly.
It's got some aluminum square tube frame with a skin on the inner and outer surfaces and a foam core in most areas.
Actually the best thing you could do.. log onto Thor's site ion teh owner's resource area. Nothing there for my older model the last time I checked. maybe you have stuff available for yours. Otherwise, call Thor's customer service and have VIN number handy.
They can tell you exactly, as well as send some drawings that at least roughly show where the frame members are, and wood panels, etc...
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