That stuff lasts forever.
My brother patched a hole in his Honda Nighthawk engine block in 2011/2012 and it hasn't leaked a drop since.
I've fixed tons of stuff over the years and wouldn't hesitate to use it for something as minor as the window regulator.
1950 Chevrolet 3100 (Ol' Roy)
1939 Packard Standard Eight Coupe (The Phantom) | 1956 Cadillac Coupe de Ville (The Bismarck) | 1964 Ford Galaxie 500 coupe |1966 Ford Mustang (Little Red) | 1969 Pontiac GTO (The Dishpit) I 1979 Ford F-100 | 1976 Ford F-150 (Big Red) | 1995 Ford F-150 (Newt)
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