It shouldn't have their is just plain sheet metal under the seal. However in each corner their is a hole that the factory made for some reason when they were building the cars. They are usually filled with paint and body filler, it is possible that one could have come un plugged.

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1969 280SE
2027 Ram 1500
2026 Genesis GV70
2007 Tiara 3200
1988 Egg Harbor 37
1981 Boston Whaler 17