Is 20 gauge OK for general body patches?

jos51700 said

I've heard that the the '73 and newer had thinner gauge sheet metal to off set weight for fuel economy, and that is why those cars seem to rust more.

But I don't know if that's true

Click to expand...

The metal on my 75 duster seems no thinner than my 69 dart, but as for the quality of the steel? I know the steel in my 79 F100 was very soft, especially noticeable in the bolts I would snap, half the body bolts in it were old dodge bolts in it by the time I sold it, figured something happened to steel quality in the 70's