I removed the seat base in my 2004 Stratos when I replaced the carpet. The metal seat base has two cutouts along the bottom where it meets the floor. On mine the seat base is carpeted along with the floor so it is difficult to see the drainage openings. It definitely does not drain as fast as an open floor drain but I would not cut a hole in that floor to drain the water. You do not know what you might cut into.
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