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Chimera I had a hole poked in my floor from running over a chisel on the highway which would cause some ingress and lots of moisture. I had great success in removing wetness and mildew by using Damprid hanging packs hung off the backs of my seats. They'd collect like a liter of water each after about a week.
Also, best place to buy them is Home Depot / Lowes. Everywhere else marks them up like crazy.