In defense of PO's everywhere up north, who did the "cave and pave" style work... I lived up there in the '60's and it would have taken thousands of craftsmen working around the clock making steel patch panels to keep up with the damage done by salt. It was a Spring ritual to re-slather the eyebrows on my mother's '58 Chevy with fresh bondo and fiberglass. I had a '67 Mustang that I dared not put anything in the trunk for fear it would fall thru the bottoms of the quarter panels on a curve. We usually traded off a car when either our feet went thru the floorboards, or the door bottoms were gone and the skin rattled. There was simply no hope of beating the salt until plastic fender liners and galvanized steel came into production cars.

 

Ross, we never used sheet metal to fix our floors. Roofing shingles worked much better. They didn't rust, and they stuck themselves to the floor when it got hot. Rust repair and sound deadening in one package. I'm surprised they didn't mention that in ehow. Maybe because you can't solder them in.