Also if you wanted to fill the seams, which Im sure 20yo truck will leak from, are the seams of the cabs when they assembled them.
https://www.amazon.com/dp/B007Q0ZQGK/?coliid=I715SF3TG0T10&colid=34SYGWWRA9HX3&psc=0&ref_=lv_ov_lig_dp_it
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