Corey would be the one to talk too but I doubt your problem is pulling the boat to Fla. We've hauled a buddy's boat to Fla the past five years behind one of our diesels running in excess of 70mph and his has held up with no cracks. If you have cracks around the welds then odds are they didn't have the heat right....coming from a welder.
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I'd rather be rich than an awesome fisherman!!