You'all made me look , my newer 11K Btu Coleman has a flexible Duct from the Evaporator fan discharge & it connects to the ( until I look at a parts schematic ) I'll call it a distribution Plenum . It looks like the Boot or Duct connector is removed via the Clamp & the Cover /Plenum is unbolted to the Base.
I may get some Insulation & wrap that Boot duct , but thats about it , interesting .
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