I have a 2018 2606WS. I had some problems and had to remove the black plastic surround from the front window. There is zero insulation anywhere in the front of the camper between the fibreglas exterior and the inner cardboard wall.
There has been a thin layer of insulation in all of the TT's I've seen like that (granted it's only a few). It's usually right against the paneling on the interior wall.
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Salem 29RKSS Pushing a GMC Sierra 2500HD!
Gotta go campin!