no wise ones around here, just experienced
the pinch weld that makes up the windshield mount flange on the TF trucks is prone to corrosion over time from bad rubber seals - if it's not too bad [some of the depth of the flange left] and not extensive, just clean it up well, use some rust converter to stop any progression, a good rust proof primer/paint, and hope the rubber covers it - if it's really bad you'll hafta cut out some metal and replace it - there's no patch panels made for that area, but it's not toooo tough, just a bit of a PITA
Bill