I agree with the rigid foam, backed by cheap plywood. I bet there's a few You tube videos on the subject.. you can do it in a day, and it will save you more than the cost of materials in a short time.
The Extreme Weather Package will only help a little. Your situation requires much more.
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Doug and Patience and Shelby the mutt
2015 Crossroads Sunset Trail Reserve ST26RB
2013 Ford F-150 3.5 EcoBoost XLT Supercab 4x4
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